POTTS — POLrCH^TA. 329 



Family AphroditidaB, Blainville. 



Genus HERMIONE. 



4. Mermione malleata, Grube. 



Grube, Annulata Semperianaj in Mdm. Petersb. s6r. 7, xxv. 1878, p. 17. 

 "Willey, Polychseta, Ceylon Pearl Oyster Report, pt. iv. p. 245. 



Ileasurement. 23 mm. in length, 10 mm. in breadth ; no. of segments 28. Length of 

 dorsal setae up to 15 mm. 



Willey remarks that this species is the southern form of M. hystrlx, a conclusion 

 which I thoroughly endorse. In general the northern species attains a larger size, but 

 beyond tbis there are few differences. 



There are dermal folds in front of the elytrophore which seemed to correspond to the 

 malleiform processes of Grube. In the specimens of H. hystrix which I was able to use 

 for comparison the state of preservation was too bad to determine the presence of such 

 folds. 



An account of the condition of the ventral setse may be usefully inserted here. 

 Willey merely remarks with regard to them that they are " furcate . . . with or without an 

 accessory tooth." In the second parapodium there occur ventral setae only, of a ditferent 

 type to the rest (cp. Hermione hystrix described by Claparede, op. cit. i. pi. 1. fig. 2 c). They 

 are slender setae, 30-40 in number and pennate or plumose (" sole pennee "). In the third 

 parapodium there is one furcate seta with 7 accessory teeth between tip and spur, and 

 another with the single accessory tooth. In the fourth parapodium the dorsalmost has 

 two accessory teeth, and in all the others there is one (dorsal) with a single accessory 

 tooth and two others which are smooth between tip and spur. This arrangement is very 

 similar to that described by Mcintosh for H. hystrix, where the ventral setae of the 

 anterior segments were yet more spinous. This is probably a very variable feature. 



Locality. A single specimen from Amirante, E 16, 39 fathoms. 



Genus PONTOGENIA. 



5. Fontogenia chrysocoma, Baird, var. mittuta, var. n. (Plate 20. figs. 26,27; 

 Plate 21. figs. 35, 36.) 



Measurements. 18 mm. long and 7 mm. broad ; no. of segments 84. 



It is hard to decide whether the two specimens here described should be placed in 

 the Mediterranean species F. chrysocoma * or in F. indica, described by Grube from the 

 Philippines +, and Willey from Ceylon J. In general appearance and size and in the 

 number of paleae they recall the latter. They possess 15 pairs of elytra in common with 

 F. chrysocoma, in distinction to the 18 paii-s of the other species ; and since the differences 

 between these forms from Zanzibar and the last-named species may be principally 



* Claparede, 'Les Annelides Chetopodes da Golfe de Naples,' pt. i. p. 314, pi. 1. fig. 3. 

 t Grube, 'Annulata Semperiana,' in Mem. Petersb. ser. 7, xxv. 1878, p. 18. 

 J Willey, in Herdman, ' Ceylon Pearl Oyster Report,' pt. iv. p. 246. 



