BEANIA 409 



This material agrees with Busk's descriptions and specimens. The pair of horn-like 

 processes on the operculum described and figured by Jullien are constantly present. 

 The gigantic avicularia mentioned by Hincks (1885) are present in several Falkland 

 specimens. 



A specimen collected at the Falkland Islands on 22 April 1927 (U.S. National 

 Museum) has an ancestrula similar to that of Beania costata var. maxilla (see below). 



Examination of specimens from Port Phillip Heads in the Bracebridge Wilson collec- 

 tion (97.5. 1 -383, 384, 386), identified as B. costata and agreeing very exactly with 

 MacGillivray's description and figures, confirms Kluge's opinion that the Australian 

 species is distinct. It appears to be very closely related to B. discodermiae (Ortmann) 

 (see p. 410). The spines are rather numerous and there are usually two springing from 

 the distal wall, behind the oral ones which are on the edge of the opesia. The avicularia 

 are within the range of variation described by Harmer (1926, p. 415) but the very 

 large ones are not present. 



2. Beania costata var. maxilla (Jullien). Fig. 33 B, C. 



Diachoris maxilla Jullien, 1888, p. 74, pi. vii, fig. 3, pi. xi, fig. 4. 

 Station distribution. Sub- Antarctic: South Atlantic Ocean, St. WS 85. 

 Geographical distribution. Tierra del Fuego (Jullien) ; Falkland Islands (Discovery). 



This form is so closely allied to Beania costata that I regard it as a variety. The chief 

 difference is in the processes on the operculum, which are branched. They may appear 

 irregularly stellate as in Jullien 's figure (pi. xi, fig. 4), or the distally directed branch 

 may be the most highly developed (Fig. 33 B, C). There are other differences of slight 

 systematic value, namely, the presence of three (instead of two) pairs of erect distal 

 spines, the shorter zooecia, and the smaller avicularia. Except on the ancestrula 

 (Fig. 33 B) the spines in my material are longer than those figured by Jullien and 

 resemble those of B. costata. 



Some of the rootlets, like those of B. inermis and other species (see p. 411), have a 

 branched tip and, as in B. discodermiae and B. petiolata (see Harmer, 1926, pp. 415, 

 416), a proximal lateral rootlet is sometimes present, in addition to the more distal 

 median one. 



The ancestrula (Fig. 33 B) is like the other zooecia in shape, but has shorter, more 

 erect, spines. From the clearly defined flattened area on its basal surface one may 

 deduce that it was encrusting. All the other zooecia have a curved basal surface which 

 was clearly unattached. 



Waters (1889, p. 4) gave this form as a synonym of B. quadricornuta (Hincks, 1885, 

 p. 245), an Australian species. Hincks does not show any opercular processes, there are 

 only four oral spines, and his figured zooecia, which are close together, do not become 

 narrower in the region of the operculum as do those of the present specimen, and 

 several of those figured by Jullien. In view of these differences, and of their wide geo- 

 graphical separation, and in the absence of undoubted specimens of B. quadricornuta 

 for comparison, it seems best to treat them as distinct. 



