78 DUBLIN UNIVERSITY 



and still more for his friendly MSS., assistance, and counsel. Some ad- 

 ditional terms I have adopted from Dr. Allman's excellent " Memoir on 

 the Fresh- water Poly zoa." As any accurate information with regard to 

 the geographical distribution of these forms is of importance, I have in- 

 corporated with those collected by Dr. Harvey one or two smaller col- 

 lections, sent to him with Alga) from various parts of the world. A 

 series, lately procured by Dr. Joliffe in New Zealand, is very interesting. 



I began an examination of foreign Polyzoa and Zoophytes in the hope 

 of falling in with some clue to the affinities of some Palaeozoic forms, and 

 especially of the Graptolitcs. In this I have hitherto been disappointed. 

 Although the Graptolites appear in some respects to approach the Po- 

 lyzoa ctenostomata, they have still peculiarities which are apparently 

 inconsistent with the structure and mode of growth of any living order. 



In Dr. Harvey's collection the Cyclostomata and Ctenostomata are 

 few in number. The Hydroid Zoophytes are very numerous, and most 

 interesting. They are in progress of illustration. 



The second part of this communication will conclude the Cheilosto- 

 mata. 



Class.— POLYZOA. 



Order 1. — P. infundibulata. 

 Sub-Order 1. — Cheilostomata. 

 Sect. 1. — Articulata. 

 Subsect. 1. — Uniserialaria. 



Family 1. — Catenicellidae (Busk). 



Genus 1 .— Catenicella (Blainville). 



As usual in collections from the other side of the Equator, the Cate- 

 nicellae are prominent and abundant. Most of the species in the " Rat- 

 tlesnake" collection are repeated, and seven undescribed forms occur. 

 One new species belongs to the fenestrate division ; the second differs so 

 completely from every described form as scarcely to be referable to any 

 of the formerly characterized groups, though occupying a position to a 

 certain extent intermediate between the two first : four are vittate ; and 

 the seventh, though distinctly a Catenicella, and closely allied to C. aurita 

 (Bmk), simulates to a certain extent the structure of the remarkable 

 genus Calpidium. 



