294 Eev. T. Hincks's Catalogue of Zoophytes 



3. C. syringa, Linn. 

 Common, on other zoophytes, &c. 



4. Reticularia, Wyville Thomson. 

 R. serpens, Hassall. 



Very common : on the stems of the larger Sertulariadae, 

 especially of S. abietina ; on the surface of bivalve shells. 



The species presents a very different appearance in these two 

 habitats*. When developed on shell, there is none of the 

 crowding of the cells which makes it so difficult to distinguish 

 their form and arrangement. 



Reticularia is nearly allied to Calicella dumosa. Its repro- 

 ductive organs have not been observed ; but an apparently kin- 

 dred Australian form, which I have lately described under the 

 name of Lineolaria (Annals for April 1861), produces very large 

 spinous capsules, which are decumbent and adnate, like the 

 cells. 



5. CoppiNiA, Hassall. 



C arcta, Dalyell. 



Not uncommon in deep water, on the stems of Plumularia 

 falcata and Sertularia abietina. 



Order HYDRIDJE, Huxley. Fam. Hydriadae. 



Hydra, Linnseus. 



1. H. viridis, Linn. 

 In the neighbourhood of Exeter. 



2. H. . 



I can only state at present that a second species of Hydra 

 occurs near Exeter ; but whether it be the vulgaris or the oli- 

 gactis, or whether both these species occur, I cannot say with 

 confidence. 



A very large and handsome Hydra, tapering (I think) to- 

 wards the base, is met with on water-plants in the Exeter 

 Canal, which may prove to be the latter of these two species. 

 Another, found some years ago in pits at Exwick, I supposed 

 at the time to be H. vulgaris. I must leave the point for future 

 settlement. 



* Vide " Note on Reticularia immersa," Sec., Ann. & Mag. Nat. Hist, 

 for 1856, vol. xviii. p. 469. 



