some British Polyzoa. 209 



iiTPgular margin, but would appear to have a lip-like 

 projection (fig. 7). 



'i'lie calcareous shells of tlie Annelidan genus Ditrupa are 

 dredged in extraordinary profusion on some parts of tlie 

 "Haaf" off Shetland. I had saved a large box full of 

 specimens of these, selected on account of encrusting growths 

 on tliem, mostly of Polyzoa. On examining the contents of 

 this box, which contained at least two thousand Ditrupcp, I 

 discovered in one specimen the Terebrijpora which I have 

 here described. 



Schizoporella Alderi (Busk). 



This species is subject to some variation in its mode of 

 growth and in the absence or presence of lateral avicularia. 

 It lias been several times described. The original illustra- 

 tions of Busk are very good. The following will give the 

 synonymy of the species : — 



Var. a. — Chain-like growth ; without avicularia. 



1856. Alysidota Alderi, Busk, Quart. Journ. Micr. Sci. vol. iv. p. 311, 



pi. ix. figa. 6, 7. 

 1869. Alysidota Alderi, "i^ormaxi, "Last Report Dredging Shetland," 



Brit. Assoc. Rep. for 1868, p. 306. 



Var. b. — Chain-like growth ; with avicularia. (Chiefly 

 arctic, rare Shetland.) 



1867. Mollia vulgaris, forma ansata (partim), Smitt, "Kritisk Furteck. 



&c.," ffifvers. K. Vet.-Akad. Forband. p. 15, pi. xxv. fig. 81. 

 1860. Schizoporella Alderi, Ilincks, Hist. Brit. Marine Pol3zoa, p. 243, 



pi. xxxvi. tigs. 9, 9 a. 



Var. c. — Clustered growtli ; without avicularia. (Shetland, 

 &c) 



18C0. Lepralin Barleei, Busk, Quart. Journ. Micr. Sci. vol. vii. p. 143, 



pi. xxvi. tigs. 1, 2. 

 1867. Mollia vnU/mis, forma ansata (partim), Smitt, I. c. figs. 79, 82. 

 1880. Schizoporella Alderi, Ilincks, /. c. fig. 10. 



Var. d. — Clustered growth ; with aviculariii. (Arctic.) 



1867. Mollia vulijuris, var. ansata (partim), Smitt, I. c. fig. 80. 



1900. Schizoporella Elmwoodifc, Waters, " Bryozoa from Franz Josef 



Land,"' Journ. Linn. Soc, Zool. vol. xxviii. p. 66, pi. '\x. tigs. 1 ^fc 13. 

 190o. Schizoporella Stormi, Nordgaard, Ilydrog. and Biol. Invest., 



Invert. Xorwig. Fiords, p. 166, pi. v. figs. 1, 2. 

 1906. 5<A/z<)/we//« i7w?i'(WjV<?, Kluge, Ergauz. u. die 'Olga' Exped. 



gcsnmm. Bryozoen, p. 40. 

 IIKK). Schizoporella Stormi, ^oxA'^wmA, Brvozoa from Second ' Fram ' 



Expcd. 1898 1902, p. 17, pi. i. figs. 10, 11. 



