524 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



genital region. In Brisingella there are always 2 gonads to each ray, 

 and although they may be branched each gonad has but a single 

 aperture on the side of the ray at a little distance from the base (see 

 Sars, 1875, pi. 1, fig. 12a). 



Brisingella includes the following species: B. fragilis (Fisher), 

 B. coronata (G. O. Sars), B. exilis (Fisher)), B. pusilla (Fisher), 

 B. tenella (Ludwig), and probably the following species described 

 by Sladen; B. verticillata, B. armillata^ B. discincta, and B. mem- 

 hranacea. B. mediterranea (Perrier) probably belongs in this genus, 

 although the gonads are not described. 



In his paper entitled Researches on the Structure and Affinity of 

 the Genus Brisinga, based on the study of a new species, Brisinga 

 coronata, George Ossian Sars describes and beautifully figures the 

 anatomy of Brisingella coronata and Binsinga endecacnemos. The 

 former is a typical Brisingella, and the special differential charac- 

 ters are clearly shown on plate 3 (several figures of the gonads in 

 situ and removed) and plate 4, figures 4, 5, 6 (characters of first 

 adambulacral, marginal, and interradial plates) ; plate 5. figures 1, 

 2, 11, 12, 15 (same ossicles). For comparison, plate 7 of the same 

 work is valuable, as the serial gonads (fig. 18) and the plates of the 

 actinostomial ring and base of rays (figs. 2, 5, 8, and 9) of Brisinga 

 endecacnemos are clearly shown. Figure 18 may be compared with 

 figure 4, plate 3; figure 7 with figure 1, plate 4; figures 8 and 9 with 

 figures 4, 6, and 5, of plate 4. 



BRISINGELLA FRAGILIS (Fisher). 



Plate 156, figs. 3, 3a. 



Brisinga fragilis Fisher, 1906, p. 1115, pi. 46, fig. 1; pi. 48, figs. 3. 3a-c. 

 Brisingella fragilis Fisher, IQllf, p. 423, figs. 5 and 6, p. 427. 



One specimen from station 5123, east of Mindoro, 283 fathoms, 

 green mud ; 8 detached rays, only. 



There is no disk, so that the number of rays can not be ascertained. 

 The secondary costae are almost obsolete as in variation A described 

 and figured in the above citation. There seems to, be only 1 (adoral) 

 furrow spinelet throughout the ray, and 1 comparatively small 



subambulacral spine, the formula being — . or ^ + I. In typical 



V V 



fragilis the first few adambulacral plates have an aboral furrow 



spinelet thus — ^-, this extending a variable distance along the ray 



in the varieties. The pediccllariae of the Philippine specimens are 

 like those of the Hawaiian. 



Type-locality. — Station 3824, south coast of Molokai Island. Ha- 

 waiian Islands, 222-498 fathoms, coral rocks, broken shells. 



Distribution. — Hawaiian and Philippine Islands, 253-387 fathoms. 



