from the North Pacific Ocean, 439 



hydrotheca is covered by the little neck of the hydrotheca 

 following it inferiorly, and it is rare to see a little space 

 between them, whilst in the preceding species the interval 

 always exists. 



The gonopliores (PL XVI. fig. 7) are in great numbers, 

 oval, ribbed on the surface, furnished with a round aperture 

 placed at the extremity of a very small cylinder ; they are 

 arranged in three series. 



Length of the colony about 60 millims. ; width of a branch 

 0*6; length of the hydrotheca 0*5, their breadth 0*27; length 

 of the gonangia 1*2, their breadth 0"55. 



This pretty species is most nearly related to Selagmoj)sts 

 pinnata, from Avhich, however, it differs in habit, in the mode 

 of ramification and, especially, the subdivision of the branches, 

 as also in the absence of intervals between the hydrothecai 

 which follow each other in the same series. 



4. Selaginopsis thujas sp. n. (PL XVJ. figs. 8-10.) 



Trophosome. Hydrocaulus straight, angular, spiral, divided 

 into internodes bearing branches which spring from all sides 

 of the principal stem and are attached by means of a tubular 

 process of the latter. Each branch divides at a certain dis- 

 tance from the point of attachment into two, each of which 

 subdivides again into three branchlets, thus forming a complex 

 of six hranches. Hydrothecai more or less conical, broad and 

 round at the base, a little narrowed at the apex, arranged in 

 six or seven series. Aperture without teeth or angles, round or 

 oval. 



Gonosome. Gonopliores sparse, oval, truncate at the apex, 

 and narrowing gradually to the base. 



Locality. Northern Pacific Ocean, 



In habit this species (PL XVI. fig. 8) is just like Thujaria 

 thuja. The whole colony is cylindrical, only a little narrowed 

 towards the apex. The hydrocaulus is divided into regular 

 internodes by deep annulations, and bears on all sides short 

 tubes, spirally arranged, to which the branches are attached. 

 Each branch (PL XVI. fig. 9) divides only at a certain dis- 

 tance from its point of attachment, which is very characteristic 

 of this species, and distinguishes it from Selaginopsis decem- 

 serialis, to which we shall refer hereafter. The branch first 

 of all divides dichotomously into two parts, each of which is 

 in its turn formed by three small branches nearly of equal 

 length. Width of the branches moderate. Colour greyish 

 brown ; that of the principal stem dark brown. The hydro- 

 thecse are arranged in several series^ the number of which is 

 not constant ; but usually a branch has five series at its base, 



