380 MR. G. S. BRADY ON NEW OR IMPERFECTLY 



conspicuous tubercles along the ventral margin, in place of the simple ridge which 

 characterizes the present species. C. arachnoidea bears also small tubercles at the 

 points of intersection of the surface network, and another row of them just within the 

 finely serrated anterior border. 



I have inscribed this species to my friend the Rev. A. M. Norman, whose numerous 

 contributions to carcinology and other branches of science are widely known, and to 

 whom I am indebted for much valuable help in the study of natural history. 



20. Cythere scabra, Von Munster. (PI. LXI. fig. 8, a-d.) 



Cythere scabra, Von Munster (1830)^ Jahrbuch fur Mineralogie, p. 63. Bosquet, Entom. Fossil, 

 des Terr. Tertiair. de la France, p. 105, pi. 5. fig. 7- (?) Egger, Ostrak. der Miocan-schicht, 

 p. 26, t. 4. f. 10. 



Carapace oval, broadest in front. Extremities well rounded. Dorsal and ventral 

 margins slightly arched. Dorsal outline ovate. Surface thickly covered with spines, 

 which vary considerably in size, and give a rough, bristling appearance to the whole 

 shell. 



Length (Atlantic) ^g-in. (1mm.), (Abrolhos) :^3 in. (-78 mm.), (Crete) ^in. ('57 mm.). 



Hab. Atlantic, 2050 fathoms (Com. Dayman) ; Abrolhos ; Crete (mud) 360 fathoms 

 {Capt. Spratt). 



21. Cythere parkeri, n. sp. (PI. LXII. fig. 1, a-e.) 



Quadrilateral, convex, once and a half as long as broad. All the margins gently 

 arched, and terminating in obtuse angles. Dorsal aspect broadly oval ; margins slightly 

 serrated : a stout, blunt tooth or tubercle on each valve in the position of the anterior 

 hinge. The lateral separated from the ventral surface by a rounded keel or angle. End 

 view subpyramidal ; angles rounded ; lower border flat. Surface pitted. 



Length ^ in. (-.571 mm.). 



Hab. Australia. Several specimens. 



I have pleasure in inscribing this species to W. K. Parker, Esq., to whom I am 

 indebted for the opportunity of describing many of the species noticed in this paper. 



22. Cythere compacta, n. sp. (PI. LXII. fig. 3, a-d.) 



Carapace subtriangular, scarcely once and a half as long as broad. Anterior extre- 

 mity broad, obliquely rounded ; posterior narrow, angular. Ventral margin convex ; 

 dorsal margin highest at anterior third, arched, somewhat angular. Dorsal outline 

 oval, with truncate extremities. The ventral ridge is most conspicuous behind, where 

 it crosses the shell transversely in an irregular line, and is continued along the dorsal 

 margin. End view subquadrilateral. Surface marked by strong reticulations enclosing 

 large quadrangular pits. 



Length -^^ in. (-508 mm.). 



Hab. Turk's Island (shallow water). 



