27 
1862. Polymastia mam(m)illaris Bwk. 
(Bowerbank, Phil. Trans. CLII). 
1863. Suberites appendiculatus Bals. Criv. 
(Balsamo Crivelli, Atti della Soc. Ital. V.) 
1867. Peneillaria mammillaris Gray. 
(Gray , Proceed. R. Soc. pag. 502.) 
? 1879. Rinalda arctica Merejk. 
(de Merejkowsky, M&em. Acad. St. Petersbourg, XXVI, 
pagg. 4—15, tabb. I, II, IM). 
[Non: 1806. Spongia mamillaris OÖ. F. Müller; 1842 Halichondria 
mammillaris Johnst.] 
To see also: 
1866. Bowerbank, Monogr. Br. Spong. II, pag. 71. 
1866. Schmidt, Zweites Suppl. Sp. Adr. M. pp. 12 and 13; 
Tab» LT, tee: .Il"and'12. 
1870. Schmidt, Spong. Atl. Geb. pag. 51, Tab. VI, fig. 3. 
1874. Bowerbank, Monogr. Brit. Spong. III, pag. 31, Tab. XII. 
1877. Marenzeller, Coelent. etc. der O. U. Nordp. Exp. pp. 13 
| and 14. 
Special description. 
 Bowerbank, in his description of Polymastia mammillaris , (Monogt. 
II, pag. 73) says that he has seen original specimens of Montagu’s 
Spongia penicillus. For that reason I think one may accept with: 
sufficient security.... (if not, you may always have doubt, and 
never be sure!) that his Polymastia mammillaris is really identical 
with M’s specimen. „I have compared the specimens sent me by 
Mr. Hyndman, from Larne Lough, with the type of Montagu’s 
Spongia penicillus, in the possession of Dr. Grant, and there is 
no difference between the two, either in external appearance or in 
structural characters’. And further: „No reasonable doubt therefore 
remains, that the specimens dredged by Messrs Thompson and 
Hyndman in Strangford Lough, in 1835 and sent to Dr. Johnston 
and those dredged by Mr. Hyndman in Larne Lough which are 
sent to me, are identical with Montagu’s Spongia -penicillus,, and 
are therefore entitled to be considered as correct types of Johnston’s 
