648 Bkady and Norman — Monograph of the 31anne and Freshwater Ostracoda 



The mandibular limb is furnished at the base with a hirsute masticating 

 lobe, which is not cleft; first joint of palp having one seta about the middle of 

 the front margin, a pair of longer setae further on, and at the extremity a single- 

 joint laminar appendage, which is as long as the second joint and bears two setae, 

 the hinder margin has three setae, and a greatly developed, ringed and filiferous 

 sensory seta, which is longer than the whole of the rest of the limb ; second joint 

 very short, triangular, no setae on front margin, on the hinder a fascicle of three, 

 of which one is ciliated ; third joint equal in lengtli to the two preceding, 

 narrow and gradually tapering distally, front margin densely setose, except the 

 distal third, hinder margin with only three small setae, two of which are at the 

 extremity; last joint scarcely separable from the preceding, ending with two chief 

 ungues, and two of smaller size. 



The first maxillae bear three lateral lobes, which partially overlie each other 

 and end in setae of varied form, but most of them of spine-like character, and 

 densely ciliated ; there is also a laminar appendage directed forwards, and 

 furnished at the base with a downward-pointing lobe and ending in two setae, 

 a third on the front margin ; the joints of the palp (which is incurved at the 

 extremit)'^) are furnished with numerous spines and setae of varied sti'ucture, some 

 of the largest being pectinated on one side. The second maxillae end in five 

 lobes, three of which are lateral and two terminal ; they are fringed with 

 variously-formed setae, those of the last lobe being for the most part strongly 

 pectinated on one side ; the ^penultimate lobe is armed with a graduated 

 series of six narrow, upright teeth,* strongly denticulated on the inner margin, 

 and curved at the extremity ; beyond the last lobe, already described, is a three- 

 lobed palp, the middle lobe the widest, ending in five setae; the others are 

 narrow, the lowest has three setas, one of which is lateral and the others distal, 

 the furthest with two distal setae ; to the outer side of the limb is attached a large 

 semicircular thin vibratory lamina, edged all round with long plumose setae. The 

 penultimate limbs or third maxillae end in three setiferous lobes, the outer side 

 of the limb carries a sub-triangular vibratory lamina, margined at first with nine 

 plumose setae, beyond which the margin is simply finely ciliated, while near the 

 further angle are three more plumose setae. 



The vermiform limb bears very numerous spines, of which there are more 

 than twenty at the end, and 9—13 on each side, each furnished with 5—6 pairs 

 of distal spinules. Caudal lamina armed with nine ungues, which gradually 

 increase in length from the first to the last, and are all finely ciliated on the edge. 



The male is rather smaller than the female, the general form including that of 

 the rostrate process is as in the latter sex, but the hinder extremity differs slightly, 



* These are so buried among the setee that they are difficult to detect, and it requires an object-glass 

 of one-eighth to maka them all out clearly, though the two upper aud larger may be easily seen. 



