7-4 Description of Genera and Species. 



The eye is relatively smaller than in C. s'ocialis, but evidently placed in the same 

 relative position beneath the pent-house formed by the blunt rostral protuberance and 

 the fold of the test representing the orbital spine. 



The antennules have a long peduncle as shown in fig. 1 1 , but not so long relatively 

 to the carapace as in the type species. It may be as well to mention here that the 

 shale in which the fossils are embedded has been subjected to some sort of interstitial 

 movement of its particles, so that the forms which are orientated with the longer 

 axes more or less conforming with the direction of movement are abnormally 

 elongated, and those that lie athwart that direction are equally abnormally broadened. 

 A mean has therefore to be struck between the two in studying the proportions. 

 In the form that lies across the direction, the length of the peduncle of the anten- 

 nule is not affected. Notwithstanding its abnormal broadening it is not so massive 

 as that of the type species. The basal joint is much the longest. The second joint 

 is longer relatively to the basal joint than in the former species; the top joint is also 

 elongated and supports two llagella of about equal length and about half the length of 

 the peduncle. Of the antennary system the distal joint of the basal part is longish and 

 extends well in front of the carapace. The scale is long and comparatively narrow and 

 caridean in construction, with strengthening keel and spine, and extending to beyond 

 the end of the second joint of the antennular peduncle. The peduncle of the flagellum 

 is not so long as the scale, and the flagellum is moderately slender, and longer than those 

 of the antennule. The body of the mandible is seen to be in place in fig. 1 1 by the bulge 

 it makes beneath the carapace and not by being crushed in. The palp is seen in the 

 same figure between the basal scale and the crushed limb, but its details are not suffi- 

 ciently well preserved. The maxillas are unknown. The maxillipedes and legs are seen 

 all crushed up together. The exopods of at least seven legs are shown. The 

 endopodites must have been long, especially those of the last trunk segments. The 

 distal joint of none is exhibited, as all the limbs are obliquely truncated in the one 

 specimen. The other specimen shows the bases of seven or eight limbs on the one side, 

 the other joints being removed. The most interesting structures preserved in this pa;rt 

 of the trunk are the brood pouches with enclosed eggs or larvae as shown in the 

 broadened specimen in "fig. 11. These occur just beneath the posterior lappet of the 

 carapace and behind the base of the forwardlj^ directed legs of tiie last trunk segment ; 

 but the carapace is somewhat displaced relatively to the tail, while the tail itself is 

 broken and pushed forward upon itself. The brood pouches, notwithstanding, are in 

 their proper relative position where they might be expected to occur. They are placed 

 relatively where the egg-sacs of the recent Nictiphanes are found. If they represent 



