Jheringnlîi paulensis, a new generic Type of Macrothricidæ. 13 



movable and incurved lamella, carrying on the tip 3 thick 

 and densely ciliated setæ extended towards the mouth. To 

 each maxilla a rather strong muscle passes from above, 

 easily observable in the lateral view of the animal (fig. 1). 

 The exact examination of the legs is one of the most 

 difficult points in the anatomy of the Clodocera, and in most 

 cases therefore, these limbs have been left unexamined and 

 more generally not even indicated in the figures given. The 

 difficulty arises not only from the very complicated structure 

 of these appendages, but also from the circumstance that 

 they lie closely crowded together, and are so very firmly 

 connected with the body, that it is a matter of no small 

 difficulty to obtain them isolated. Moreover, some parts of 

 them are so very delicate and fragile, as to be easily in- 

 jured by dissection. I have tried in the present form, 

 by the dissection of numerous specimens, to get a correct 

 idea of the structure of these limbs, and propose in the fol- 

 lowing pages to describe them more in detail. There are 

 5 pairs present, which are all very dissimilar in structure, 

 the 2 anterior pairs being much more strongly built than 

 the 3 posterior, and evidently to some extent adapted for 

 taking hold of algæ or other submerged objects. The move- 

 ments of these 2 pairs appear also far less regular than 

 those of the 3 posterior pairs, which are generally found to 

 perform very regular, almost rhythmical oscillations, thus 

 manifesting their respiratory character. All pairs, moreover, 

 except the last, are evidently adapted for seizing the food 

 and pushing it towards the mouth, as they are provided 

 with a well-marked, incurved masticatory lobe, clothed with 

 peculiar setæ. Besides this lobe which forms a direct . 

 expansion of the stem proper, the 3 chief parts, well- 

 known in Crustacea, viz., endopodite, exopodite and epi- 



