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Show 1904.] MARINE FAUNA OF ZANZIBAR. 289 wide, from 10 fathoms in Wasin Harbour, East Africa; and one, larger, 6 m m . wide, dredged off N. Male Atoll, Maldives, from 35 fathoms, bottom sand. This species is nearly related to the two following, but is readily distinguished from E. afra by the early commencement of the gills, and from E. coccinea by their persistence to the end of the body. I The specimens correspond very closely and in detail with the account given by Gravier. The body is flat anteriorly, immediately behind the buccal segment, though arched dorsally behind. The shortness of the segments immediately following the head is also a feature of note. In the smaller specimens the annulation of the tentacles is not so easily seen as in the larger. These also differ in the jaw-apparatus, which in the younger are delicate and calcareous, in the adult dark brown. The ends of the lower plates, however, remain white, thus, as in their shape, exactly resembling those of E.flaccida. The forms of the other plates call for no remark, and the following are the formulae of their teeth :-6 - 7 : 6 + 8 - 8 and 5 - 5 : 7 + 7 - 9 ; the latter corresponding closely with that given by Gravier. The gills usually begin at the third foot, but in the two East- African specimens rather later, viz. at the seventh or eighth. It is impossible not to regard with great doubt the distinction drawn by Gravier between this species and Grube's E. longicirris from Suez. The annulation of the appendages varies in distinctness in these specimens, in the largest of which it can be made out in the anterior dorsal cirri as in Grube's species. The length of the tentacular cirri, which in Grube's specimen reach to the anterior border of the prostomium, may be abnormally great, though in one of these the cirri reach well beyond the anterior border of the buccal segment. When a complete specimen is examined it is seen to be true for these, as for Grube's example, that most of the gills reach scarcely half the length of the dorsal cirrus. The larger anterior ones anteriorly are of about the same length, which, allowing for a reasonable amount of variation, corresponds with both Grube's and Gravier's accounts. However, the brevity of the latter gives enough uncertainty to justify the creation of a new name for these specimens, until Grube's work can be verified and completed. EUNICE AFRA Peters. (Plate XX. figs. 1-5.) Eunice collaris Grube, Annulata Semperiana ; Gravier, Nouv. Arch, du Mus. de Paris, 1900, p. 251. Eunice perrieri Gravier, loc. cit. p. 232. Eunice mutabilis Gravier, loc. cit. p. 245. For other synonymy see Ehlers, Nachr. zu Gott. 1897 *. This species, among the least specialised of the genus, besides * In a note on this species just received, Dr. A. Willey gives E.paupera Gr. as vet another synonym. PROC. ZOOL. Soc-1904, VOL. I. No. XIX. 19 |