GENUS 01* TERRESTRIAL tSOPODA. 443 



In tlie first pleopod of the male (fig. 14) the male organ is about two-thirds 

 as long as the narrow endopod, which is grooved on its posterior aspect ; the 

 exopod is short and not produced at its inner side, its extremity being 

 regularly rounded. 



The second pleopod of the male (fig. 15) has the endopod extremely long 

 and slender ; the exopod is somewhat produced at its inner angle, and has 

 a few very delicate plumose setae on the outer margin. 



In the female the exopod of the first pleopod (fig.. 16) is short and broad 

 with regularly curved margins, its extremity is slightly produced on the 

 inner side and is broadly rounded; no endopod was seen. 



Tlie second pleopod of the female (fig. 17) has the exopod larger with 

 inner angle more produced, margins with a few delicate setce ; the endopod 

 forms a short triangular process. 



The uropoda (fig. 18) are practically the same as in D. echinata. 



Deto armata, Budde-Lund. 



Deto annata, Budde-Lund, 1906, p. 86, pi. 4, figs. 26-36. 



Sj)ecific description. — Similar to D. echinata, but smaller and somewhat 

 narrower. Head, each segment of perseon, and third and fourth segments of 

 pleon each bearing a pair of spines which are much larger in the male than 

 in the female ; general surface minutely granular. Terminal segment with 

 apex triangularly produced, subacute. 



Antennae long, slender, fourth joint of flagellum of moderate size. 

 Maxillipeds with the palp a little longer than the masticatory lobe Legs 

 supplied with moderately long spines. Pleopoda and uropoda apparently as 

 in D. echinata. 



Length 12 mm. 



Habitat. St. Paul's Island, Indian Ocean ; collected by Grerman South- 

 Polar Expedition in 1903. 



I have not seen specimens of this species, and have drawn up the specific 

 diagnosis from the description and figures given by Budde-Lund. 



The species appears to be very similar to D. ecldnata, but differs in having 

 a pair of spines on the third and fourth segments of the pleon as well as on 

 the perseon. Budde-Lund says nothing about the length of these spines, 

 but if the specimen he figures is a male (as it presumably is), they are not 

 so long as in fully grown specimens of D. echinata; Budde-Lund, however, 

 gives the length of the animal as 12 mm. only, and the specimen figured may 

 not be fully grown. 



The mouth-parts, perseopoda, and pleopoda of this species have been 

 figured by Budde-Lund ; they appear to present a close general resemblance 

 to those of D. echinata and D. acinosa. 



