MARINE ZOOLOGY 



temperature, together with a considerable number of periodic migrants, 

 which are attracted from the south in early summer, and probably from 

 the north and east in autumn, owing to the peculiarities of temperature 

 which characterize East Anglian waters in those seasons. Purely 

 northern or purely southern types are exceptionally scarce in the resi- 

 dent Norfolk fauna. 



Out of a total of thirty-one recorded hydroid zoophytes two only 

 can be said to have a restricted distribution, viz. the southern Coryne 

 vaginata and the northern Sertularia ftlicula. 



Out of twenty-six recorded Polyzoa two only are northern types, 

 viz. Menipea ternata and Cribrilina annulata, and five are more or less 

 southern types, viz. Scrupocellaria scrupea, Bugula plumosa, Membranipora 

 lacroixii and monostachys, and Amathia lendigera. It appears to be particu- 

 larly significant that Bugula purpurotincta^ a close relative of E. plumosa, 

 but a purely northern type, has not been obtained south of Flamborough 

 Head, though abundant along the coast from Scarborough to Wick. 

 The creeks and waters of East Anglia appear to be the headquarters of 

 Membranipora monostachys, which nowhere attains such luxuriance of 

 growth and numbers as here. 



Out of twenty recorded chstopod worms all are common wide- 

 ranging forms, except Eulalia sanguinea and possibly Sabellaria spinulosa, 

 which are distributed principally to the northward. 



In the following records I have relied principally upon the reports^ 

 of the surveying cruise of the German ship Pommerania in the summer of 

 1872 [Jahresbericht d. Commission z. wiss. Untersuchung d. deutschen Meere 

 in Kiel, ii. and iii. 1875). The valuable information in these reports has 

 been supplemented from notes or specimens communicated to me by 

 various Norfolk naturalists, among whom I desire to thank especially 

 Dr. S. F. Harmer of Cambridge ; Mr. H. D. Geldart, Mr. Thomas 

 Southwell, and Mr. R. A. Todd of Norwich ; and Mr, A, Patterson of 

 Yarmouth, for their kind and willing assistance. 



CCELENTERATA {Jellyfish, Sea Anemones, etc.) 



Stinging animals, of circular outline, having all their organs radially arranged round a 

 central mouth ; free-swimming {e.g. medusas) or sedentary {e.g. hydroid zoophytes, sea 

 anemones) ; solitary {e.g. medusae and anemones) or subdivided into ' colonies ' by budding 

 {e.g. hydroid zoophytes). The units in the colonies are known as polyps. 



I. HYDROZOA 2. Hydractima echinata (Fleming). 



I, Hydroid Zoophytes Incrusting the shells of univalves (esp. 



Colonial, forming arborescent or encrusting f.""™"'"^^"^^^!?!^^^,"^"^^'^ ''^ ''^""''' 

 stocks, attached to stones, shells, worm-tubes 



crabs. Off Yarmouth (P. 



and seaweeds. 3. Coryne vaginata, Hincks. 



Nomenclature : Hincks, British Hydroid Zoo- Cromer (H. D. Geldart) ; Hasborough (R. 



phytes, 1868 (= H). A. Todd). 



I. Cordylophora lacustris, Allman. 4. Hydranthea margarica, Hincks. 



In brackish or fresh waters. Near Kings Off Yarmouth, growing on Flustra foUacea 



Lynn (Dr. Low). (Dr. S. F. Harmer, 1899). 



1 For the sake of brevity the Pommerania records are indicated in the sequel by the letter P. 

 79 



