128 H. J. HANSEN. 
mens 8:0 and 6°4 mm. in length ; in these two young specimens 
the processes at seventh thoracic sternite are very short, but 
yet distinct, while no trace of appendix masculina on endp. 
of plp.? could be perceived in any of them. These immature 
specimens resemble Cymodoce in general aspect; in both 
seventh thoracic tergite has a broad but very short protu- 
berance as arudiment of the plate in the adult male; in the 
larger of these two specimens the mesial process of the 
abdominal notch is broadly triangular and reaches beyond 
the lateral angles of the notch, but in the smaller specimen 
the notch is almost rectangular, with the basal margin a little 
convex, the mesial lobe being very low. Judging from these 
features, I suppose that the notch in the adult female be 
rounded as in the two preceding genera. 
10. Cassidinopsis (n. gen.).—The type is Cassidina 
emarginata (Guér.), which in many important points— 
structure of plp.* and plp.°, shape of epistome, mandibles, 
fifth jomt of maxillipeds, end of abdomen—differs strongly 
from the type for the genus Cassidina, C. typa (M.-Hdw.). 
C. latistylis (Dana) has generally been referred to C. 
emarginata as a synonym, but Dana’s figure of the end of 
abdomen does not agree well with the shape observed in C. 
emarginata; a detailed account of this species is given by 
Pfeffer (1887). No other species referred to Cassidina 
belongs to Cassidinopsis. 
C. Spheromine platybranchiate. 
1, Parasphzroma (Stebb.).—The type is P. prominens 
(Stebb.). I have examined two females with brood in internal 
pouches; they are co-types kindly forwarded me by Mr. 
Stebbing, who describes and figures a male specimen. The 
two abdominal protuberances are scarcely as high in the 
female as in the male; the exp. of urp. has the outer margin 
convex inalmost more than three quarters of its length, but its 
distal fourth is more concave than on Mr. Stebbing’s figure, 
so that the apex of the ramus is less produced, but directed 
