16 J. W. Dawson—Footprints, etc., on Carboniferous Rocks. 
as in the smaller specimens previously known ; and Ringicula 
nitida V.,* a new species allied to A. buccinea Desh., of Europe ; 
Cylichna ‘alba ; Lenin albus ; Entalis striolata St. ; ; and Den- 
talium occidentale St., ete 
mong the Crustacea were Hupagurus Kroyert Stimp., £. 
Bernhardus St., EH. pubescens St., Hyas coarctatus, Ptilocheirus 
pinguis Stimp., Harpina fusiformis Smith (St. sp.), Aga polita 
Stimp., 4. psora Bate and West., and Balanus porcatus. All 
of these Crustacea, except the species of ga, are common in 
the shallow waters of the Bay of Fundy. 
{To be continued.] 
Arr. Il.—IJmpressions and Footprints of Aquatic Animals and 
rere oie on etek, gli Rocks ; by J. W. Dawson, 
LL.D., F.R.S. 
THE footprints and other markings of aquatic invertebrate 
animals ae of fishes are necessarily, for the most part, less 
distinctive and important than those of land animals, both 
ecause less characteristic in themselves, and because reproduced 
under similar forms in very different geological periods. The 
former peculiarity has caused them to be neglected as of little 
importance, or to be confounded with impressions of plants. 
With reference to the latter, I have myself shown that the 
impressions made by the modern King-crab faithfully represent 
the Protichnites, Climactichnites, and Rusichnites of the Primor- 
dial and Silurian, and similar comparisons have been made by 
Salter, Jones, Dana and others, between the tracks of modern 
Crustaceans and worms and some of those in the oldest rocks. 
1. Protichnites Owen. 
The footprints from the Potsdam Soap in Canada, for 
which this name was proposed by Owen, which were by 
him referred to Crustaceans probably fierass cae Limulus, were 
* Ringicula ni 
itida V., 8 
Shell small, white, sda fecal oval, with five whorls, spire rapidly and regu- 
larly tapered, sub-acute, shorter than the aperture. Whorls very convex, regularly 
rounded, the sutures well impressed ; a well marked, impressed, revolving line 
n nt, microscopic revolving lines, most distinct anteriorly perture 
ewhat cre sha Outer lip evenly rounded, fo the segment of a 
circle, the border regularly thickened, ing a little posteriorly, near the suture. 
us on the narrow, nearly even, but a little swollen in the middle 
and slightly raised. Columella stout, recurved at o strong, very 
ent, equal, spir: Segre ge anterior one projecting be ond the can th 
the end roun an inch; breadth -125; length of aperture ‘10; 
same ‘043. 
Two living specimens from (0) 110 and (s) 150 fathoms, muddy bottom. 
