RHYNOBRISSUS. 213 



(or Thuva) Harbor, Viti Levu, Fiji Islands, and was collected there by Mr. 

 Agassiz, or some member of his party in 1897. The holotype (M. C. Z. 3152) 

 was ^collected by Semper at the island of Panglao, Bohol Province, Philippine 

 Islands, and came into the M. C. Z. collection in 1873. It bears Semper's 

 label "Brissus sternalis" and Mr. Agassiz catalogued it as "Metalia sternalis." 

 The third specimen, much smaller than the other two, was also collected by 

 Semper but apparently at the Pelew Islands. It bears a label in an unknown 

 hand: "Brissus maculosus Leske." The "maculosus" was subsequently 

 scratched out and "? sternalis Lam." written below. The locality is written 

 "Palaos." In the lower left-hand corner, in lead pencil, is lightly written 

 "49,35 neu." In spite of these hints that the specimen might represent a new 

 species it was catalogued as Metalia sternalis. The differences between these 

 specimens and sternalis appear to be constant and are easily seen, especially 

 when specimens of the two species are side by side. In sternalis the posterior 

 part of the sternum is carinate, the keel connecting the median culminating point 

 with a single similar point on the subanal fasciole. The prominence of the 

 keel and the culminating points show great diversity and they may be indis- 

 tinct and the sternum nearly flat, but I have seen no approach to the character- 

 istic triangle of dicrana. It is to be regretted that the color of the bare test 

 lent itself so poorly to photography that the figures given herewith do not 

 show this triangle clearly. 



Metalia townsendi. 



Eobrissus townsendi Bell, 1904. Ann. Mag. Nat. Hist., (7), 13, p. 236. 



This species is known only from specimens taken in the Arabian Sea off 

 Oman. Bell considers the subcentral position of the apical system a generic 

 character but it does not seem so to me. 



Rhynobrissus. 



A. Agassiz, 1872. Bull. M. C. Z., 3, p. 18. 

 Type, Rhynobrissus pyramidalis A. Agassiz, 1872, loc. cit. 



In view of the fact that only seven specimens of Rhynobrissus are avail- 

 able, that they seem to represent at least four and possibly five species, and 

 that only one is certainly adult, the present revision of the genus can scarcely 

 be considered final! The name was originally spelt with a y in the first syllable 

 (as above) and this spelling was retained in the Revision. In 1878 and 



