176 MESSRS. L, MURBACH AND C. SHEARER ON [June 16, 



of the greatest regularity in the arrangement of the diverticula, 

 exactly opposite one another. As a matter of fact, this opposite 

 character arises only from a crude manner of representation. 

 Probably this kind of symmetry is as little marked in them as 

 in F. penicillata or P. minuta ; for these reasons in future this 

 character should be omitted from the generic diagnosis. Fewkes 

 (14) draws the diverticula in his species opposite, yet identifies 

 it with P. penicillata of Agassiz. Our specimens approach the 

 species of Fewkes more than they do the original descriptions 

 given by Agassiz for this same species. Agassiz (2) obtained 

 P, penicillata in the region of Puget Sound, and also on the 

 coast as far south as the Harbour of San Francisco, where he 

 found it very abundant ; Fewkes collected his examples at Santa 

 Barbara and Santa Cruz on the southern coast of California. 

 He does not doubt that these southern examples belong to the 

 same species Agassiz described as P. j^&nicillata from a more 

 northern range. As already stated, this revised version of P. peni- 

 cillata by Fewkes approaches very closely P. minuta ; in fact 

 we have only ventured to give it separate specific rank on 

 account of size, a feature of no very great importance. We only 

 attach importance to it here because our form was evidently 

 mature, the great development of the gonads, the number and 

 length of tentacles making this almost certain. Yet the height 

 of the bell is 15 mm. in P. minuta, as compared with 40 or 50 mm. 

 in the P. jjenicillata of Agassiz and Fewkes. While Fewkes 

 identifies his species with that of Agassiz, as already stated, if his 

 drawings and descriptions are accurate there would seem to be 

 striking difi^erences between the two. Some of these are the 

 shape of the bell, which is broader, a less developed condition of 

 the divei'ticula on the ends of the radial canals next the circular 

 canal of the bell-margin, the club-shaped even branched ends of 

 these diverticula, the position of the gonads on the part of the 

 radial canals descending to the stomach, while Agassiz (2) states 

 they are " attached at the highest point of the four chymiferous 

 tubes." 



Agassiz figvires ibuv gonads in each group, and these reach 

 halfway to the velum ; Fewkes figures eight, and these reach 

 almost to the level of the velum. Although Agassiz only figured 

 four gonads, Fewkes says he subsequently found their number to 

 be much greater. We should hesitate, however, in emphasising 

 these distinctions, for Fewkes, as assistant to Prof. Agassiz, had 

 doubtless ample opportunity of referring to the original specimens 

 and notes of Agassiz. 



Agassiz considers his species to be the same as that described 

 by Eschscholtz (11) under the name of Melicertum penicillaium, 

 p. 106. Eschscholtz gives a very short description and poor 

 figure, from which it is hard to determine anything exact. It was 

 found by Eschscholtz on the coast of California. Haeckel (18) 

 follows Agassiz in arranging this species under P. penicillata, 



