256 Prof. J. C. Schiodte on the 



17. On examining the elongate head of the Anthura from 

 beneath, after having separated it from the body, we observe 

 at once a convex, broadly ovoid part situated in the middle, 

 and reaching from the base so far forward as to occupy about 

 half the length by nearly half the width of the entire head. 

 At first sight one is tempted, by the shape and position of this 

 piece, to take it for the stipites of the maxillipeds ,• but on 

 closer examination it turns out to be immovably connected 

 with the head all round ; further forward the maxillipeds, too, 

 appear developed in all their component parts ; the ovoid 

 protuberance must therefore be the prosternum, which thus in 

 Anthura is distinguished by a very unusual size. The an- 

 terior margin of this large prosternum forms a transversal line, 

 presenting a shallow sinus on either side, in which the cai'do 

 of the maxilliped is fixed, whilst the stipites of the maxillipeds 

 fit through a kind of articulation into two deeper indentations 

 in the middle of this same margin. The two maxillipeds lie 

 so close together that the interior margin of the left stipes 

 and of the first joint of the left palpus overlaps a little the oppo- 

 site edge of the right stipes and of the first joint of the right 

 palpus. In this way the two limbs together form an oblong 

 duct, open above and reaching forward, almost on a level 

 with the prosternum, to the base of the mandibular lobes. 

 The first joint of the palpus has parallel sides and is one third 

 longer than wide ; the stipes is longer than the joint just 

 mentioned, and at the apex of equal width Avith the latter ; 

 but its exterior margin is considerably dilated in the middle, 

 while contracted near the base, in consequence of which a 

 triangular space is left between the exterior margin of the 

 stipes and the prosternum ; and this space is filled by the 

 triangular cardo of the maxilliped. In this manner the pro- 

 sternum with the cardo, stipes, and first palpus-joint of each 

 maxilliped form together a continuous whole, a sort of semi- 

 cone projecting from the under surface of the head. With this 

 other parts are combined. The second and last joint of the 

 palpus of the maxilliped forms a small triangular leaf, the 

 outer margin being convex, the inner margin concave ; like 

 the first joint, it is furnished with short sparse fine hair, a few 

 longer and stronger setce occupying the inner side. On 

 account of this configuration, this joint does not approach 

 closely to the corresponding one on the other side, but an 

 elliptic slit is left between their interior margins, whilst their 

 anterior, rounded margins touch closely on the upper lip. 

 This latter hangs down almost perpendicularly from the large, 

 conoid, strongly projecting clypeus ; and its anterior margin 

 presents a broad sinus. Taken together, all these parts con- 



