Dr. H. Woodward — M. Cambrian Fossils of the Rockies. 543 



collected from a band of shale of Middle Cambrian age at Mount 

 Stephen, near Field Station on the Canadian Pacific Railway. Two 

 of these specimens were collected by Mr. E. G. McConnell, of the 

 Geological Survey of Canada, in 1888, and the remainder by 

 Dr. H. M. Ami, of the same Survey, in 1891, The species seems 

 to have been somewhat gregarious in its habits when living, for 

 upwards of twenty specimens of it are exposed on the surface of 

 a large slab of shale collected by Dr. Ami at this locality, and 

 fourteen upon that of another. It is associated with numerous 

 species of Trilobites, Brachiopoda, etc. All the specimens of 

 A. Canadensis are crushed quite flat laterally, and occur as obscurely 

 defined and extremely thin carbonaceous impressions of the body- 

 segments, with the tail (the latter usually a little twisted) on each 

 of the surfaces exposed by splitting pieces of the shale. 



"The generic name Anomnlocaris (from ai'o/noio?, 'unlike' ; Kctpii, 

 ' a shrimp ' ; i.e. unlike other shrimps) is suggested by the unusual 

 ehape of the uropods or ventral appendages of the body-segments 

 and the relative position of the caudal spines. 



" Ten genera of Phyllocarida have previously been recorded as 

 occurring in the Cambrian rocks of Europe or America. These 

 include Ceratiocaris, McCoy (1848), Hymenocaris, Salter (1853), and 

 Protocaris, Walcott (1884). To these may now be added Anomalo- 

 caris, which differs from the other three genera of Cambrian 

 Phyllocarids in the following particulars: — In Ceratiocaris the 

 caudal appendages consist of a median telson or style and two 

 lateral stylets. Further, although ventral appendages to the body- 

 segments have been discovered in one species of Ceratiocaris, the 

 C. stygia of Salter, yet these are represented as ' broad and paddle- 

 shaped,' not slender and acutely pointed ^ as in Anomalocaris. In. 

 Jlymenocaris, according to Professor H. A. Nicholson, the 'hinder 

 termination of the body is adorned with three pairs of unequal 

 spines,' but in the woodcut of the type and only known species of 

 that genus, the H. vermicauda, which is reproduced in so many 

 palaeontological manuals, all of these spines are represented as 

 terminal and the body-segments as devoid of any ventral appendages. 

 The first specimens of Hymenocaris, by the way, were collected by 

 Dr. Selwyn in 1846 in the Lingula Flags near Dolgelly, Merioneth- 

 shire. The Protocaris MarsTiii of Walcott, from the Middle Cambrian 

 of Vermont, is described as having no fewer than thirty narrow 

 segments ' between the posterior edge of the carapace and the 

 telson,' and a telson ' which supports two caudal spines.' " (J. F. W.) 



We are prevented by want of space from giving, as we had hoped 

 to do, a complete summary of the Mount Stephen fossils, and must 

 here conclude our imperfect sketch of this most interesting fauna, 

 expressing the hope that the Canadian Geological Survey will before 

 long publish the whole series in a monograph form. 



^ After a careful study of Mr. "WTiymper's specimens I am inclined to think these 

 acutely pointed and spine-like appendages may have been fringed with fine hairs, of 

 which I have here and there detected traces. 



