In 1851 Logan took to London a small slab of sandstone and a plaster cast of a 12 ½ foot slab from a quarry on the left bank of the river St. Louis, at the village of Beauharnois and on April 30, 1851 both he and Professor Owen read papers before the Geological Society of London.
In 1852 Logan took to London three slabs and 100 casts (in total, about 350 feet of track). One of the slabs, 12 ½ feet in length, was the original of the cast he had taken in 1851.
In a paper read March 24, 1852 before the Geological Society of London, Logan described the geology of the area and the finding of five new localities of foot-prints. Two localities were in the vicinity of Beauharnois: the first, in the field of Mr. Henault, a half mile west of the quarry in which the first impressions were discovered; the second, two and a half miles further west at the mouth of the Beauharnois Canal. The other three new locations were in the vicinity of Point Cavagnol (about 15 miles west of the first locality – the quarry in the village of Beauharnois); on the Island of St. Généviève in the St. Lawrence River, south of Montreal Island (about 7 miles north of the village of Beauharnois); and on the Riviere du Nord, at Lachute, in the Seignory of Argenteuil (about 35 miles north east of the first locality).
In a paper also read March 24, 1852 before the Geological Society of London, Professor Owen (1852) described and named six tracks, stating that he had selected from the casts and slabs that Logan had brought to London “the best marked and most intelligible portions for [his] descriptions.” Logan (1863) noted that in view of the “various differences in the tracks, Professor Owen has given separate specific provisional names to several of them, not for the purpose of indicating a positive specific difference in the animals which have impressed them, but for the convenience of reference.” Professor Owen distinguished between two different genera and four different species.
The six tracks that were named by Professor Owen and which in his paper were accompanied by plates showing the tracks, follow:
1. Protichnites septem-notatus Plate IX
2. Protichnites octo-notatus Plate X
3. Protichnites latus Plate XI
4. Protichnites multinotatus Plate XII
5. Protichnites lineatus Plate XIII
6. Protichnites alternans Plate XIV
Copies of those six plates form part of my March 7, 2014 blog posting. They are shown together below.
Five of those named tracks came from Mr. Henault’s field. The sixth, Protichnites multinotatus, came from near the first one discovered, namely the track at the quarry on the St. Louis River at the village of Beauharnois.
Professor Owen included a seventh plate, Plate XIV.A, remarking that it is for a slab “the casts of which were first brought over by Mr. Logan during the preceding year.” Plate XIV.A therefore shows part of the original 12 ½ foot specimen described by Logan (1851) and Owen (1851) and taken to London in 1852. It is shown below.
To understand why Professor Owen named six tracks it helps to translate the Latin names (provided in Billings, 1857) and to consider part of his Owen’s description:
1. Protichnites septem-notatus - seven marked - a repeating pattern of fourteen impressions of footprints, seven on the left of the medial line and seven on the right
2. Protichnites octo-notatus - eight marked - a repeating pattern of sixteen impressions of footprints, eight on the left of the medial line and eight on the right
3. Protichnites latus - broad - “the impressions of the feet are deeper and larger”, the track would seem to have been made “by a different species having a body broader in proportion to its length
4. Protichnites multinotatus - many marked - “ a strong deviation of the intermediate groove from the mid-line between the two lateral series of impressions”
5. Protichnites lineatus - linear - the median “impression preserves in some parts... a considerable and equal depth; ... the lateral impressions... are represented by continuous grooves rather than by a succession of pits.”
6. Protichites alternans - alternate - “the opposite impressions of the series are not symmetrical; for where the impressions are widest apart on the left, those on the right...are nearest together... These impressions indicate a waddling gait, or an alternate oblique movement side to side...”.
It is also helpful to consider the following drawing of Protichnites septem-notatus from Owen (1860) where he has circled the repeating sets of seven footprints.
While Owen (1852) described the tracks in detail, I find his descriptions hard to follow. The best description is by Logan (1852b at pages 10 - 12):
“The track and footsteps, when the specimens are most perfect, in general present a median groove more or less flat, and of different proportionate widths in different specimens, with a number of footprints on each side in answering pairs; certain sets or numbers of these answering pairs have homologous repetitions throughout the whole length of the track, as if they were the result of successive applications of the same impressing instruments, and the numbers of answering pairs in the homologues of different tracks are sometimes different, constituting something which may be considered analogous to difference of species. The homologues in different tracks appear to have sometimes seven and sometimes eight answering pairs of pits, and it is difficult to say whether the pits are to be taken as impressed by the extremities of so many legs, thus giving the animal fourteen legs in the one case, and sixteen in the other, or whether some of the impressing points are to be grouped in twos or threes, .... The median groove in most of the tracks is so uniformly in the middle between the footprints, as to favor the supposition that it may be occasioned by the effect of an immoveable breastplate or plastron, but in one remarkable instance, at a bend in the track, the groove gradually leaves the middle, and while it seems impressed with more than usual force, approaches and partially obliterates the footprints on the convex side, as if the impressing part had been the extremity of a tail, which, when the body turned to one side, interfered with the footprints in the rear, on the other. A feature common to all the grooves is, that each repetition or homologue of the footprints is accompanied with a deepening and shallowing of the groove, giving it the appearance of a chain of shallow troughs, which, when the impression is light, are separated from one another by intervals of the ungrooved surface. The groove is often but faintly indicated, and occasionally it is not perceptible; and frequently it happens when this occurs, that the footprints are stronger and deeper than when the groove is more conspicuously impressed. In some of the tracks, while the groove is straight, the exterior limits of the footprints offer a congeries of segments of a circle, convex on the outside, but those on opposite sides of the groove alternate, the segment on the one side, starting from the middle of the segment on the other, and giving to the whole series of footprints in the track a serpentining course, as if the animal had waddled in its gait. In one of the tracks there are three narrow grooves instead of footprints on each side, of the main one, for a certain distance, as if the limbs of the animal had been dragged along the bottom, while the body was afloat. ... The generic term for the whole is Protichnites, and the specific names are, P. septemnotus., P. octonotatus, P. multinotatus, P. alterans, P. lineatus.”
A Plan of Mr. Henault’s Field at Beauharnois
Logan (1852) included a plan of Mr. Henault’s field at Beauharnois, the source for five of the six Protichnites specimens figured by Owen (1852). Below is an edited version of Logan’s plan of the field.
Note that the scale is in chains (1 chain = 22 yards = 66 feet = 20.1 Meters); that the plan shows the direction of ripple marks on the bedding; that I’ve shown the tracks in magenta; and that the tracks are on a number of different bedding planes.
Logan (1852) reported ten tracks in area A, seventeen tracks in area B, six tracks in area C, and ten tracks in an area that is a few yard to the east of area C. Within a length of four chains (about 90 yards or 80 meters) Logan found 43 tracks.
All of the 43 tracks were between 4 inches and 6 1/2 inches wide, except for one that was 3/4 of an inch wide. The longest track is 28 feet six inches long while the shortest was one foot long. Twenty-six of the tracks from areas A, B and C were on smooth surfaces while seven of the tracks from areas A, B and C were on ripple marked surfaces. (For the fourth area Logan did not identify the surface.)
Logan (1852) included additional plates showing closeup views of areas A, B and C. Amended versions showing parts A and B are provided below. Logan numbered each track on Part A and Part B and in his paper provided the length and width of the tracks. Logan's plates also included numbers (that I've shown in blue with a blue square) corresponding to Owen's names for the tracks.
The plan of part A shows the tracks that are numbers 1, 5 and 6 of Professor Owen’s descriptions, namely:
1. Protichnites septem-notatus (seven marked)
5. Protichnites lineatus (linear)
6. Protichnites alternans (alternate)
For part A, seven of the tracks were on a smooth-surfaced bed, while two of the tracks (Logan's 9 & 10) were on a surface 2 inches lower showing ripple-marks, while the tenth track (Logan's 8) was "on a surface still lower by about 1 inch, but showing no ripple-mark."
The plan of part B shows the tracks that are numbers 2 and 3 of Professor Owen’s descriptions, namely:
2. Protichnites octo-notatus (eight marked)
3. Protichnites latus (broad)
Of the seventeen tracks on part B, twelve tracks are on a smooth surface and five tracks (Logan's 13, 14, 15, 16, 17) are on a ripple marked surface 2 inches below the smooth one.
Logan (1863) provides various measured sections of Potsdam sandstone, including a section from Beauharnois in the vicinity of Henault’s field (1863, pages 105-106), where he describes the beds and indicates where ripple marks, wind marks, Protichnites tracks and Scolithus occur. Based on his observations, Logan (1860) suggested that “The crustacean which impressed the tracks at Beauharnois must have been a littoral animal..."
Additional Locations for Protichnites Trackways Provided by Logan
Subsequent to giving his talks in London, Logan provided other localities where Protichnites tracks were found:
- Protichnites, at Perth, Ontario in association with Climactichites (Logan, 1863, pages 93 and 107);
- in Lansdowne and Bastard township, Ontario (Logan, 1852b, page 10)
- “about a mile N. W. of Cuthbert's mills on the Chicot there is an exposure of fine grained white sandstone, characterized by Protichnites” (Logan, 1863, page 93);
- Protichnites, on a peninsula on the north side of the Ottawa River, about seven miles below the mouth of the Petite Nation, (Logan, 1863, page 94);
- in the vicinity of Pointe du Grand Detroit in Vaudreuil, twelve miles west of the locality at the Beauharnois canal (Logan, 1863, page 90);.
Murray (1852, page 67) provides the best description of the tracks from near Pointe du Grand Detroit:
“[A]bout twenty-five acres above the Pointe du Grand Detroit, fine grained white quartzose sandstones were met with in beds of from six inches to two feet thick. Some surfaces displayed ripple-mark, and on one, trails and footprints of a species of animal exist, similar to the tracks occurring at Beauharnois, in the same description of beds. The largest of the tracks measures eight and a-half inches across, and the trail is visible for four feet, and gradually becomes obliterated at end. On the same surface, twenty yards farther up the stream, three additional tracks of the same sort were observed, each-one traversing the other two; two of these measured four inches across, and the third four and a-half inches; the last is distinct for three feet in length, and the other two, one foot eight inches, and one foot three inches respectively. The groove in the middle between the footprints on each side, so frequently seen at Beauharnois, occurs only in one of the smaller trails.”
I have provided his full description, because most of the tracks were missing the groove in the middle and now would be identified as Diplichnites.
Pointe du Grand Detroit is now better known as Quarry Point and falls in Hudson, Quebec. The stream that Murray referred to is likely the Vivery River/Vivery Creek.
Additional reports of Climactichnites and Protichnites Trackways from Beauharnois
Others have reported on Climactichnites and Protichnites trackways from Beauharnois, including
Walcott (1914 at pages 261 and 277 ), who collected specimens from “Rogier’s farm just west of the town of Beauharnois”. Yochelson and Fedonkin (1993) mention that “an exceptionally large slab containing numerous examples of both Climactichnites and Protichnites were collected from ‘a mile west of Beauharnois, Quebec’” by Walcott. This is the large slab that is the frontispiece to their article and was at the date of their article “on public display off the east side of the Rotunda on the first floor of the National Museum of Natural History, Smithsonian Institution, Washington, DC.”
Clark and Usher (1948) reported that a quarry in Potsdam sandstone at Melocheville, which is about 3 km to the west of the original quarry at Bearharnois, had specimens of Climactichnites exposed on the quarry floor.
More recently, Lacelle, Hagadorn and Groulx (2012) reported on Climactichnites and Protichnites trackways in the Keeseville Formation of the Potsdam sandstone at Beauharnois, together with other trace fossils, from which they concluded that “these fossils were produced in shallow marine to intermittently emergent sand-dominated coastal environments, with tracemakers occupying pools, channels, levees, floodplains, and on windy sand flats.”
Even more recently Splawinski, Patterson and Kwiatkowski (2016) reported Diplichnites trackways in the Cairnside formation of the Potsdam sandstone at Beauharnois, Québec, noting that they found “sedimentary structures and trace fossils indicative of supratidal, intertidal, and shallow-marine lithofacies.”
Christopher Brett
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Addendum
Briefly Consider the following.
Two Protichnites tracemakers walk into a bar. One says to the other “I’d lost track of you.”
Two Protichnites tracemakers walk into a bar. One comments on his friends disheveled appearance, and is chastised “What do you expect, I was caught in the Cambrian Explosion!”
Three Protichnites tracemakers walk into a bar. Two of them should have ducked.
A Protichnites tracemaker walks into a bar, orders a scotch on the rocks, and the bartender asks “Any particular kind?” The tracemaker replies “Any single malt whisky on quartz arenite– littoral or eolian is fine. I’m not particular. ” (Is that just being siliclastic?)
What did the Protichnites tracemaker say when it ran into a long lost friend while exploring the eolian sand dunes? “Long time no sea.”
If a paleontologist gives a talk commenting on Logan’s Holmesian reasoning in deducing that Protichnites tracemakers inhabited tidal flats, should the paleontologist conclude with the statement “Sedimentary my dear Watson”?
Why is it hard to interview a Protichnites tracemaker? All they want to do is make tracks.
Ichnologists are dogmatic. It’s as if everything is written in stone.
Did you hear about the absent minded Ichnologist that was studying Protichnites? He kept getting off track.
Sir William E. Logan was a great fiction writer. The problem is that everyone takes him littorally.
The theory that the Protichnites tracemaker was a trilobite is not that far fetched. It should get equal Billings.
Did you hear about the Protichnites tracemaker that was tired of sleeping on sand? He bought a Walcott?
Do Protichnites tracemakers travel light because they don't Owen anything?
Did you hear that Protichnites tracemakers went on strike for equal treatment with Climactichnites tracemakers? They wanted a resting trace.
When the Protichnites tracemaker asked the Climactichnites tracemaker why it didn’t venture inland, the Climactichnites tracemaker responded “Tidal flat. Sand dune hilly.”
Did you hear about the Euthycarcinoid that disappeared without a trace? Probably not.
Did you hear about the Protichnites tracemaker that was always contradicting itself? Kept saying “That’s not what I sediment.”
Why don’t Protichnites tracemakers commit crimes? They’re easy to track down.
Did you hear about the foolish Euthycarcinoid that robbed a bank? The police were able to trace the funds.
Did you hear about the Euthycarcinoid that was born on the wrong side of the tracks? He made good.
Protichnites tracemakers were too vain to hang out with Trilobites. They didn’t want to become dated.
If a fossil is defined as a markedly outdated or old-fashioned person or thing, why does the study of Ichnology never get old?
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