448 



the first 2 segments of mesosome uonibined, rostral iirqjeotion short but distinct, 

 lateral corners subtruneate at the tip. Anterior pairs of coxal plates not very 

 broail, and rapidly increasing in size to the 4th pair, which are narrowly 

 truncated at the tip, and scarcely as broad as they are deep. Last pair of 

 epimeral plates of metasome produced at the lateral corners to a small, but 

 distinct, recurved point, posterior edge considerably curved. Eyes rather 

 large, especially in the male, and obliquely oval in form, pigment dark 

 brown. Superior antennse about equalling '/s of the length of the body, Ist 

 joint of the peduncle not attaining the lengtli of the other 2 combined, last 

 joint about half as long as the 2nd, and having the terminal lappet quite 

 short, with only 2 calceolae, flagellum not quite twice the length of the 

 peduncle, and composed of about 20 articulations, the 1st of which is the 

 largest. Inferior antennae scarcely exceeding in length the superior, and 

 having the llagellum but little longer than the peduncle, its 1st joint rather 

 large. Anterior gnatliopoda with the carpal lobe rather narrow and but 

 sparingly setous, propodos oblong ovate in form, about twice as long as it 

 is broad, ])alra nearly twice as long as the hind margin, from which it is 

 but very slightly defined, its edge nearly straight, and armed in its posterior 

 half with f) strong denticles; dactylus moderately strong and .slightly curved. 

 Posterior gnatliopoda somewhat larger than the anterior, otherwise of much 

 the same structure. Pereiopoda not very strongly built, and edged with 

 fascicles of slender spines, basal joint of the 3 posterior pairs oval in form, 

 with the posterior edge evenly curved and quite smooth. Last pair of 

 uropoda with the rami fully twice as long as the basal part, the inner one 

 being a little larger than the outer and very acutely produced at the tip, 

 its inner edge densely spinulose, and having besides a series of ciliated setae. 

 Telson narrow linguiform, fully twice as long as it is broad, and nearly of 

 equal breadth throughout, tip evenly rounded. Body semipellucid, with a 

 yellowish violet tinge, and mottled with irregular specks of a clear orange 

 hue, each segment being, moreover, bordered posteriorly by a narrow band of 

 a dark, reddish-brown pigment; on the anterior part of the back occui's, 

 besides, a rather conspicuous rounded shield of a silvery lustre, occupying 

 the dorsal face of the 3rd and 4th segments of mesosome. Length of adult 

 female scarcely exceeding fi mm. 



lle))iarls. — The aljove-described form, which I believe is that recorded 

 by Zaddach as Ampliitho'e Rathkei, has generally been confounded with the 

 next species, being considered as only a small variety. On a closer exami- 

 nation of both forms, both in the living state and preserved, I have, however, 

 found certain minor difi'erences between the two, which would seem to warrant 

 their specific difference. Thus the colour is rather ditFerent, as also the form 



