On the Anatomy of t)arwiiiclla Stevensoni. 117 



Cytherura Sarsii, Brady. PI. IV. figs. 6, 7. 



We figure here what appears to be a local variety of this 

 species, the outline being somewhat less angular than usual. 



Cytheridei's subulata, va,i\fasciata, nobis. PI. V. figs. 1-5. 



This differs from the typical form in having a conspicuous 

 broad black band across the shell in front of the middle, and 

 also in the reticulated structure of the shell, which is repre- 

 sented in fig. 5. The anterior margins of the valves (fig. 4) 

 are crenulated. 



Paradoxostoma cuneatum, n. sp. PI. V. figs. 6, 7. 



Carapace, seen laterally, oblong, subreniform, rather higher 

 behind than in front ; height equal to less than half the length ; 

 anterior extremity evenly, posterior obliquely, rounded ; 

 superior margin gently and evenly arched, inferior slightly 

 sinuated in the middle. Seen from above, the outline is com- 

 pressed, cuneate, greatest width near the posterior extremity 

 and equal to one third of the length, tapering gently toAvard 

 the anterior and abruptly toward the posterior extremity, both 

 of Avhich are subacuminate. Surface of the shell smooth. 

 Length -^ inch. 



A few specimens of this species were dredged at New 

 Grimsby Harbour and inside St. Mary's in depths of from 

 10-15 fathoms. 



Note on the Anatomy of Darwinella * Stevensoni. 



Our first description t of tliis curious Entomostracan being 

 made from specimens which had been dried, and in which the 

 contained animal could be very imperfectly seen, was incorrect 

 in several important ^particulars. We propose now to rectify 

 as far as we can our former errors, having, through the kind- 

 ness of the Rev. J. Gunn of Norwich, been supplied with spe- 

 cimens of DarioineUa in the fresh state. To that gentleman 

 we wish here to express our cordial thanks for the assistance 

 which he has both now and on other occasions given to us. 



From the details of structure given below it will be seen 

 that Dar-winella occupies a position intermediate between the 

 two families Cypridge and Cytheridge, though more nearly 

 approaching the latter family. The points of divergence are 



* Our first generic name Pulycheles having been previously apnropriated, 

 was withdrawn in favour of" Darwinella (see Ann. & Mag. Nat. Ilist. 

 ser. 4, vol. ix. p. 50, .laniiarv 1^72). 



t Ann. & Mag. Nat. Hist'. July 1^70, p. 25. 



