390 Mr. H. J. Carter on the " Tubulations Sableuses " 



sion in the median line extending throughout the bodj, resem- 

 bling that of the dorsal vessel of an Annelid, together with 

 a similar appearance of the lateral branches in one part, if 

 they are not due to the grooves of segmentation, and, lastly, a 

 conical tail ; while the typical specimen, first described, pre- 

 sents a cylindrical form of the same size in the upper half 

 and inflated in the lower one, with the anterior extremity 

 truncated and the posterior reduced to a point — the core or axis 

 consisting of a distinct cylinder and the surface tuberculated. 



But, although the axial cylinder when extricated from the 

 tuberculous layer, is almost exactly like that of Trachyderma 

 serrata, what are we to deduce from the all-enveloping tuber- 

 culous layer itself and the circular cylinder with branches ? 

 To me they are without analogy, although the rest of the 

 facies, together with their having, in some instances, gone 

 down into the arenaceous deposit a whole metre in length, is 

 characteristic of an Annelidan type and habit. 



Phillips instituted the genus Trachyderma (Mem. Geol. 

 Survey, voh ii. pt. i. p. 331, pi. iv. figs. 1-4) for two species, viz. 

 T. coriacea and T. squamosa. Of the former it is stated that 

 the rings on the cylinder are "protuberant or tubercled" 

 (fig. 1), and of the latter that they " rise at regular distances 

 into short small cariniform projections ; " while Salter {I. c. 

 fig. 9, a) shows that the Budleigh-Salterton (Silurian) fossil 

 possesses the remains of a series of inclined conical lateral 

 processes arranged serrately. So that in the latter there was 

 something beyond or outside the central cylinder, which cen- 

 tral cylinder, as in the common earthworms {Terricola), pro- 

 bably represents the alimentary canal only, i. e. without the 

 annulated integument, while the tuberculous layer might have 

 been analogous to the branchial tufts in Arenicola piscatoruni 

 among the Dorsibranchiata. 



Be this as it may, under the circumstances it seems best to 

 consider this fossil, provisionally, as a new type of Annelids, 

 for which I would propose the name of Broeckia^ after M. 

 Ernest Vanden Broeck of Brussels, who has taken such trou- 

 ble in sending me the specimens. The genus would then 

 stand thus : — 



Genus Beoeckia. 



BroecMa hruxellensis. (PI. XVIII. figs. 1-8.) 



Fossil cylindrical, truncated in front, abruptly pointed or 

 conical behind, tuberculated on the surface ; upper half equal 

 in transverse diameter throughout ; lower half gradually in- 

 flated towards the middle (PI. XVIII. fig. 1). Composed of a 



