444 



MR. G. S. BRADY'S MONOGRAPH OF 



Carapace of the female, as seen from the side, subquadrangulav ; height equal to half 

 the length. Anterior margin rounded, posterior produced above the middle into a wide, 

 obliquely truncate beak ; superior and inferior margins nearly parallel, the former scarcely 

 arched, the latter slightly sinuated in front of the middle. Outline, as seen from above, 

 boat-shaped, ventricose ; greatest breadth in front of the middle, and equal to half the 

 length, acuminate behind. Surface of the shell waved and, on the ventral surface, longi. 

 tudinally striate. 



Length ^ in. ■ 



Hub. Berwick-upon-Tweed [Rev. A. M. Norman) ; Peterhead {Mr. D. Robertson). One specimen from 

 each locality. 



11. Cytheruiia Robertsoni, n. sp. (Plate XXXII. figs. 16-18.) 



Carapace of the female, as seen from the side, subovate, produced into a lateral ala 

 behind the middle of the ventral margin ; height equal to more than half the length. 

 Anterior margin rounded, posterior forming a slight and somewhat rounded protuberance 

 above tlie middle. Superior margin gently and evenly arched, inferior slightly sinuated. 

 Seen from above, the outline is subrhomboidal, broadest behind the middle, where the 

 width is equal to about two-thirds of the length ; extremities slightly mucronate. Ventral 

 surface quite flat. End view broadly triangular, the width greater than the height, 

 basal angles much produced. Surface of the shell very distinctly and regularly marked 

 with a raised reticulation, except on the ventral surface, which is longitudinally striated. 

 The male is rather more elongated, more sinuated ventrally, and the alae not so much 

 produced. 



Length in. iH^'^^- 

 Hub. Lang Bank, Cumbrae {Mr. D. Robertson), and in rock- pools, Arran {Rev A. M. Norman). 



This is a very distinct and remarkable species ; and I have pleasure in naming it after 

 its discoverer, whose diligent pursuit of marine zoology, as well as his unvarying kind- 

 ness in assisting me Avith specimens for the preparation of the present monograph, merit 

 my most cordial acknowledgment. 



12. Cytheuura gibba, Miiller. (Plate XXXII. figs. 68-70.) 

 Cythere ffibba,"M.u[\er, Entomostraca, p. 24, tab. vii. figs. 10-12. 



gibbera, idem, ibidem (mas) ; Lilljeborg, De Crustaceis, p. 167, tab. xix. figs. 1, 2. 



gibba, Zenker, Anat. Studien iiber die Krebst. p. 84, tab. v. D. 



Scandinavian type ? Distribution: Recent — Norway, Britain. 



Carapace of the female, as seen from the side, elongated subquadrangular, of nearly 

 equal height throughout, greatest height equal to less than half the length ; rounded in 

 front, posterior margin produced into an obtuse beak above the middle ; superior margin 

 straight, inferior slightly sinuated. Outline, as seen from above, constricted in the 

 middle, forming a rounded lateral protaberance behind, widest behind the middle ; 

 greatest width equal to more than half the length ; extremities pointed, the posterior 

 mucronate. End view pentagonal, width greater than the height. " The male more 

 elongated, subreniform, upper margin slightly, lower deeply sinuated ; seen from above. 



