Contributions to the Crustacean Fauna of South Africa. 363 



the exterior only just wide enough to accommodate the crustacean 

 (i inch). It would be interesting if experiments could be instituted, say 

 with some of the common European species of Cymodoce, to discover 

 if these " dwellings " are constructed as a normal means of protection, 

 or only by a pair for the special purpose of hatching a brood in safety. 



To be determined also is the manner in which they are made, for 

 they are undoubtedly made by the crustaceans themselves. In the 

 above case, moreover, the dwelling was made deliberately, not a 

 mere taking advantage of a chance crevice or hollow in the sponge. 



White has described a Sphaeroma spongiosum which, according to 

 Hansen, has been assigned to Cymodoce in the British Museum collec- 

 tion by Miers. The species comes from Australia and presumably was 

 found inhabiting sponges, but I have not been able to consult the 

 original description. 



CYMODOCE SETULOSA (Stebb.). 



1902. Exosphaeroma setulosa Stebbiug, S.A. Crust, pt. 2, p. 68, pi. 12s. 

 1914. Cymodoce setulosa Barnard, I.e. p. 389. 



In 1914 I expressed the opinion that this " species " could not be 

 regarded as the of valida, as Hausen thought, on account of there 

 being other $ specimens more in accordance with the $ of valida. 

 I have since been able to examine 2 co-types of setulosa received back from 

 Stebbing. One of them is a $ having the appendages on the 7th 

 peraeon segment well developed and the stylet on pleopod 2 also quite 

 distinct though not separated from the ramus. Evidently therefore 

 the specimen is nearly full grown and probably no great change would 

 occur in the ornamentation after the final moult. C. setulosa must 

 consequently be regarded as a perfectly good species, the diagnostic 

 features being as mentioned by Stebbing and founded on a specimen. 



The other specimen is smaller and may be either ^ or as far 

 as one can tell. It does not help much in deciding what are the 

 characters of the 9 



CYMODOCE TUBERCTJLOSA Stebb. var. TRIPARTITA Rich. 

 (Plate XV. Fig. 28.) 



1873. Cymodoce tuberculosa Stebbing, Ann. Mag. Nat. Hist. (4), vol. 12, 



p. 95, pi. 3, fig. 1. 

 1902. Whitelegge, Sci. Ees. "Thetis," pt. 4, 



p. 258, fig. 28 (maxilliped). 



