dcsimg

Description

provided by NMNH Antarctic Invertebrates

"Cellaria scoresbyi, sp. n.
(P1. IV. figs. A-D.)
Salicornaria tenuirostris Busk, 1884, p. 92, text-fig. 12.
Not Salicornaria tenuirostriв Busk, 1852 Ь, p. 17.
Distribution.—Patagonian Region ('Challenger,' St. 314; 'Discovery,' Sts. WS. 225, WS. 228, WS. 243, WS. 246).
Specimens examined.—Numerous specimens in the 'Discovery ' Collection, 1945.8.4.1-4, 6, and a slide of chitinous parts, Busk Coll., 87.12.9.422.
Нolotype.—` Discovery ' Investigations, St. WS. 243, 17.vii.28, Patagonian Shelf, 51 °06'S., 64°30' W., 144-141 m., One slide, 1945.8.4.3.
Paratype.—St. WS. 243, unmounted material, 1945.8.4.4.
Remarks.—This species differs from true C. tenuirostris chiefly in the presence of a median longitudinal sclerite in the mandible (as shown in Busk's text-fig. 12), and in the form of the longitudinal cryptocyst ridges which commonly meet proximally in a continuous curve, thus describing about three quarters of an oval ; when the oval is interrupted proximally the portions of the ridges that are developed follow the same line (P1. IV. figs. В, C), and show no tendency to turn proximally as in C. tenuirostris.
The avicularia (P1. IV. fig. D) are remarkable for the flatness of the beak, no part of which is noticeably raised above the general surface of the branch. In true C. tenuirostris the slightly hooked beak projects a little in profile.
Rusk's ` Challenger ' material purporting to represent C. tenuirostris comprises three slides only, and no un¬mounted material. They are all labelled as from St. 314. Of these slides, one (87.12.9.422) is a preparation of chitinous parts agreeing exactly with Rusk's text-figure 12 and with the 'Discovery ' material of C. scoresbyi. The second (87.12.9.421) is a specimen of C. variabilis, a species which Busk had so clearly distinguished that one can only presume an error in his labelling. The third (99.7.1.1677) is a preparation of opercula only, the opercula differing in shape from those on the first slide, and from those of C. variabilis. It was evidently prepared from some other species. .
Mу identification of C. tenuirostris (Busk, 1884) with C. scoresbyi rests on the agreement of the chitinous parts in Rusk's text-figure, and inthe first slide mentioned above, with those of C. scoresbyi ; and on Rusk's description which particularly mentions the proximal meeting of the cryptocyst ("interior") ridges. The description is clearly not in any way based on the other two slides mentioned above. My conclusion is strongly supported by the locality." (Hastings, 1946: 229)