750 AUSTRALIAN CRUSTACEAN FAUNA, 



to a microscopic examination we find that each hair is in reality 

 a small rake in itself, having developed towards its extremity, 

 along one side, three or more small hook -like protuberances (Fig. 

 1, G). In the maxillipedes, one set of muscles serves two pur- 

 poses, as, when the maxillipede proper is moved in mastication, 

 the epipodite or flabellum being fixed to it, also moves, and then 

 in such a manner that it sweeps the gills from bottom to top, and 

 vice versa. 



In the first maxillipede this flabellum is far larger than that of 

 either the second or tliird maxillipedes. It sweeps the whole of 

 the external surfaces of the eight branchite, and also to some 

 extent the internal wall of the branchiostegite. 



(.5) Secoyul Maxillipede (Fig. 1, B). This consists of an 

 exopodite like that of the preceding appendage; a 5-jointed, rather 

 palpiform endopodite, of which the meros is by far the largest 

 joint, and the podobranchia. The flabellum in this case is a 

 slightly calcified lamella, fringed with the before-mentioned hooked 

 setse. This sweejDs the interior surfaces of the four anterior 

 branchiee and the corresponding part of the body wall. 



(6) Third Maxillipede (Fig. 1, A). This large appendage 

 consists of a 2-jointed basal portion, a 5-jointed endopodite, a 

 3-jointed exopodite, and the podobranchia. The first and second 

 joints (ischium and meros) of the endopodite are broad and 

 massive, and are coated on their inner edges with a short red 

 dense pubescence. The hairs which constitute this being stiff 

 no doubt materially assist in the disintegration of food. The 

 three remaining joints are small (they together form the 

 " endognathal palp "), and are fringed, as also is the upper edge 

 of the meros, with hairs of, I believe, a sensory nature. The 

 exopodite is divided into three parts — -a long, rather broad, basal 

 portion, having strong setse on its external border, surmounted 

 by a very short narrow joint, this being terminated by a slender 

 many-jointed antennar}' filament, clothed with very fine hairs. 

 These two terminal joints lie across, behind the meros, at right 

 angles to the long basal joint, and not in the position in which I 



