20 Description of Genera and Species. 



antennules show the same massive peduncle extending beyond the tip of the rostrum and 

 the basal scale of the antenna, and terminating in two short many-jointed lashes of 

 nearly equal length. The antennal scale is a little more expanded and shorter in 

 proportion than in the type species, and, like it, the antennal lash, to judge from the 

 portions preserved (figs. 3, 5), was massive and long compared with those of the anten- 

 nule, in tills respect differing widely from the recent Lophogastrids. The mandibles are 

 usually too much crushed to be studied, but their position is generally well shown in 

 consequence. The palp, which often extends into the surrounding sediment, is often 

 seen in specimens fossilised sideways to be three-jointed and pediform. The maxilUt 

 have not been seen in a fit state of preservation for study. Of the maxillipedes, only 

 wliat are probably the detached endopodites have been observed (fig. 1), i\I. 4816^, the 

 three last joints of which are similar to those of the type species. Of the seven pairs of legs, 

 the endopodites have all been observed. They are much as in the type species, but are all 

 proportionately shorter and thicker. The exopodites, as in the former species, have the 

 strong muscular basal joint, and terminate in strong ciliated many -jointed swimming 

 lashes (figs. 1, 4). The epipodites consist, in the females, of breeding lamellaa attached 

 to the bases of the last seven trunk limbs. These are membraneous, round 

 tipped, and edged with ciliated borders, and so large in flattened-out specimens that they 

 often project beyond the edges of the carapace as imbricating finely-corrugated plates 

 (figs. 3, 3"^), M. 4844^. The gills (figs. 3, o^, 4) are as in the former species. These are 

 seen to be constructed on the same principle as in Gnathophausia (fig. 4^), M. 4246'', 

 the branch arteries ending in lobulated blood sinuses, but the branch arteries do not 

 seem to be given off at such regular intervals as in that form, and thus in some 

 respects resemble those of the nearly allied Eucopia australis Dana, as figured by 

 G. 0. Sars in his monograph on the Schizopoda of the Challenger Expedition. 



The caudal limbs (figs. 3, 5) are constructed as in T. loudonensis, and were appar- 

 ently spatulate in their terminal swimmerets. The uropods of the sixth tail segment 

 are like those of the former species, but a little broader in proportion. The telson 

 differs considerably from T. loudonensis in having a median crest extending back to near 

 the constriction. It has also side keels or crests ending at the articulations of the two 

 accessory flattened swimmerets with which, like the former species, it was supplied. It 

 also ends in a fimbriated mesial lobe notched at the end, and set along its posterior 

 border by strong setaj or spines. 



Remarks. — It may l)e as well to make some further remarks about the specimens. 

 Fig. 1 shows one of the best preserved specimens from GuUane shore, magnified 6 

 diameters. It is fossilised with its back up, but it is fortunate that the carapace is 



