596 DR. G. S. BRADY ON 



Bairdia dubia, sp. ij. (Plate XX. figs. 1, 2.) 



The outline of the shell as seen laterally is rhomboidal (fig. 1), 

 the gi'eatest height situated near the middle and equal to half 

 the length ; anterior extremity obliquely subtruncate, posterior 

 produced below the middle into a wide, obtuse beak; dorsal 

 margin forming a flatt-ened arch, infei'ior nearly straight, gentlj'- 

 sinuated in the middle : seen from above (fig. 2) oblong, ovate, 

 twice as long as broad, greatest width in the middle, sides gently 

 curved, subparailel, extremities produced, the anterior obtusely 

 i-ounded, posterior prominent and submucronate. Surface of the 

 shell smooth, covered throughout with A^ery small, closely-set, 

 impressed, circular punctations. Colour yellowish grey. Length 

 0"65 mm. 



One specimen only, dredged in 30 fathoms. 



Aegillcecia affints, sp. n. (Plate XX. figs. 9, 10.) 



Shell, seen laterally, elongated, siliquose (fig. 9), greatest height 

 in the middle, equal to more than one-third of the length ; 

 antei-ior extremity evenly rounded, narrow, posterior scarcely 

 at all angulated ventrally ; dorsal margin foi-ming a continuous 

 even arch thi'oughout, ventral nearly straight through its whole 

 length : seen from above (fig. 10) the outline is narrowly subovato, 

 thrice as long as broad, greatest width in the middle, tapering 

 towards the subacuminate extremities, but more abruptly behind 

 than in front. Surface of the shell perfectly smooth. Colour 

 light grey. Length 0'54 mm. 



Several specimens dredged in 70 fathoms. 



The differences in form of shell between the various species of 

 Ar<jiU(ecia hitherto described appear to be extremely slight, but 

 that here figured does not seem fairly referable to any one of 

 them. 



Cythere orispata Brady. (Plate XX. figs. 3, 4.) 



Specimens of C. crispata, an extreme form of which is here 

 figured, were dredged in 70 fathoms. This form differs from the 

 type in having the extremities — and to some extent the ventral 

 margins — irregularly dentated. This condition, however, is found, 

 though to a much less marked degree, in some of the type- 

 specimens. 



These specimens seem indistinguishable from a species described 

 by G. W. Miiller — C. diffusa* ; perhaps also from C. elegans of 

 the same author. 



Cythere cixgulata, sp, n. (Plate XX. figs. 5, 6.) 



Shell, seen laterally, oblong, subquadrate (fig. 5), of nearly equal 

 height throughout, height equal to at least half the length ; 

 exti'emities well rounded, thb posterior rather the narrower, dorsal 

 margin nearly straight, inclined gently from before backward, 



* Dip. Oi^fraoofter ties Golfes von NeHpel. p. .354. 



