MUSEUM OF COMPARATIVE ZOOLOGY. 301 
The valves are of a yellowish white, and one of them shows remnants of a 
thin but rather tough greenish epidermis. 
Sugcenus TROPIDOMYA Da tt anp SMITH. 
An anterior cardinal tooth in each valve; no lateral teeth; cartilage as in 
Leiomya. Tropidophora Jeffreys, not Troschel nor Thompson. Type Neera 
abbreviata Forbes. 
This is Section I of Smith. The type has the buttress fairly developed and 
chiefly concentric sculpture. 
Susncenus HALONYMPHA Datt anp SMITH. 
An acute cardinal tooth in right valve; no other teeth in either valve; a 
clavicular rib extending posteriorly in both valves, fossette small, central; 
surface concentrically striate or smooth. Type Newra claviculata Dall. Sec- 
tion K of Smith, who places here Neewra inflata Jeffreys and N. congenita 
Smith. 
The latter appears different from anything I have seen. WN. inflata has been 
in some confusion. The specimens so marked in the Jeffreys collection in 
Washington are of two kinds. One valve from “ Porcupine expedition, 1870, 
St. 16, 17 a,” is a left valve of Halonympha claviculata Dall, fitting almost ex- 
actly the right valve which served as my type. Those from ‘ off Gomera, 
Chall. exp.,” and “ Porcupine exp. 1869, St. 39,” are Rhinoclama teres Jeffreys. 
Whether there is an ¢nflata not represented in the Washington series I do not 
know; the figures in P. Z. S., 1881, pl. 1xxi. figs. 2, 8, in which the differences 
seem a little strained, might buth have been made from varieties of teres in the 
collection. Smith notes something of the same kind in his description of 
N. teres (N. gomerensis of references to Plate X.) in the report on the Challenger 
bivalves, p. 50. 
Halonympha claviculata Datt. 
Necra claviculata Dall, Bull. M. C. Z., IX. p. 112, 1881. Smith, Chall. Rep. Lam., 
p. 52, not pl. ix. figs. 8-8b. 
Neera inflata, Jeffreys, P. Z. S., 1881, p. 942, 1882; (partly). 
Plate II. Figs. 2, 2a. 
Habitat. Station 44,539 fms., one valve; Sigsbee, off Havana, 450 fms. 
(?) fragment; Porcupine expedition, Atlantic Ocean, Station 16, or 17 a, 1870; 
Challenger expedition, Station 33, in 435 fathoms, coral mud, near Bermuda. 
In the Porcupine specimen it is clearly to be seen that the posterior muscle 
was planted on the upper surface of the clavicle, which is therefore in this case 
a myophore as well as a buttress. 
