<-.,, MR. (,. S. BRADY'S MONOGRAPH OF 



of from six to twelve small 



margin slightly rounded, and armed below witli a series 

 spin. The dorsum forms a flattened arch; ventral margin deeply incurved near the 

 middle. Seen from above, the outline is irregularly lanceolate, sharply mucronate in 

 IVoni btusrly behind, and mostly asymmetrical, on account of a want of correspondence 

 in Hie tubenulation of the valves; greatest width situated at the posterior third, equal 



to less than Imlf the length. End view somewhat pyramidal, strongly keeled below. 

 The surface of the valves is punctate, and marked near the middle with a deep trans- 

 verse furrow; the anterior half of each valve bears mostly one, the posterior half two 

 tubercles; but these are subject to much variation in position and number, scarcely any 

 two shells being precisely alike. Colour dull white or straw-coloured. Upper antenna- 

 blender, five -jointed; last joint linear, equal in length to the preceding; the third 

 scarcely more than half the length of either of the two following ; second equal to third 

 and fourth united. Terminal claws three, nearly equal in length, curved and setiform ; 

 the fourth joint bears at its apex four setae, about equal in length and strength to the 

 terminal claws, and near the middle two shorter setae. The second and third joints bear 

 e;u-h one seta. Terminal claws of the second antennae slender. Feet short and stout; 

 terminal elaws of the first and second pairs stout and strongly curved; those of the 

 third pair slender, subsetiform, and equal in length to the three preceding joints ; second 

 joint equal in length to the two following. Males unknown. 



Lemrth ,',.■ in., heisrht 



Hah. In fresh water. 



and 



berland 

 Middles 



ity Durham (Rev. A. M. Norman) ; Fulwel 

 mnty Durham ; East Belsay Lake, Northum 



(Mi 



2. Limnicytiiere monstrifica (Norman). (Plate XXIX. figs. 9-12.) 



Cypris- monstrifica, Norman, Ann. & Mag. Nat. Hist. vol. ix. 1862, p. 45, pi. hi. figs. 4, 5. 



Valves, as seen from the side, oblong sub quadrangular, strongly spinous and tuber- 

 eulate. Extremities boldly rounded, the anterior bearing on eaeh valve a marginal 

 row of about twelve sharp spines. Dorsal margin straight, angulated at its anterior 

 extremity, whence it slopes gently downwards and backwards. Ventral margin incurved 

 centrally. Seen from above, the outline is compressed, oval, each valve bearing two 

 very large spinous tubercles, and several smaller spines and ridges. End view sub- 

 quadrate, irregularly angulated. The valves are closely punctate, furrowed across the 

 middle ; one strong spinous tubercle on the anterior half, and two on the posterior half 

 of each valve. The posterior portion is also beset with numerous small sharp spines. 

 Animal unknown. 



Length i- in. 



o u " :i3 



Hah 



M. Norman) 



This species was described by Mr. Norman as a Cypris. It seems, however, to hav< 

 more affinity with the genus Limnicytiiere, to which I here refer it. Mr. Norman ob 

 serves that it made no attempt to swim in the few days during which he kept it alive 



