FOSSILS OF THE CLINTON GROUP. 547 



Coleolus Clintonensis; sp. nov. 



(Plate 37 a , Fig-. 11.) 



In the limestone at Soldiers' Home doubtful forms occur, having the 

 rate of increase of the specimens of Orthoceras inceptuni. One specimen has 

 very faint indications of transverse striae. A second has, instead, very- 

 sharp and clear-cut transverse very fine groovings, which are so regular 

 and occur at such equal distances that it does not simulate the forms of 

 O. incept inn. The failure to find either septa or siphuncle in these speci- 

 mens, even when 24 mm. long, has led to the opinion that they are Clin- 

 ton species of Coleoius, for which reason the term Coleohts Clintonensis has 

 been reserved for them. They are very rare and for this reason their 

 generic reference is not considered as satisfactory as though many speci- 

 mens had been found habitually to lack the septa and siphuncle. 



Comilaria JViagarensis, Hall. 



Plate 30 Fig. 16.) 



In the Proceedings of the Boston Society of Natural History, 1889, a 

 specimen found at Todd's Fork was identified with C. JViagarensis, Hall. 

 More recently the same form was found at Huffman's Quarry in the upper 

 shaly courses. A comparison of the two specimens enables us to make 

 the following observations. Although when flattened out so as to expose 

 two sides simultaneously this shell seems to have a considerable 

 apical angle, when in its natural condition the apical angle is seen to be 

 small. Our specimens are not perfect enough to give this apical 

 angle with exactness, but approximately in one specimen 18 mm. long the 

 diagonal diameter measured 7.8 mm. at the smaller end of the specimen 

 and 10 mm. towards the larger end. Along the four corners the shell 

 was incurved, forming a longitudinal furrow which was most distinct 

 below, but grew less distinct near the upper or larger end. The sides 

 themselves were very gently convex. 



Comilaria bilineata, sp. nov. 



(Plate 37a, Fig. 11 



A very small fragment of a species of Comilaria was found at Sol- 

 diers' Home. In it the normal simple transverse striae of this genus were 

 represented by so many pairs of very distinct striae, the pairs being 

 separated by the usual strong grooves, crossed by rather more distant and 

 less sharp longitudinal striae than in C. Niagarensis. Seven of these 

 pairs of transverse striae occupied a length of 'J. 2 mm., and 9 longitudinal 

 striae occupied a width of 1.7 mm. The name Comilaria bilineata is 

 suggested for this species. 



