NEW TYPE OF MALACOSTEACOUS CBUSTACEAN. 



11 



pointing backwards, and the base closely occupying the area between the pair of endo- 

 podites. Viewed from the side (fig. 18) the apical portion is seen to curve downwards. 

 Probably the purpose of this process is to aid in holding the female during copulation. 



Uropoda (PL 2. fig. 21). — These have, relatively to Anaspides, a longer basal part, and 

 the two branches (endopodite and exopodite) are slightly narrower and without any 

 keel or transverse suture. The peduncle is stout and projects halfway to the end 

 of the telson, with a few spines on the upper surface ; the branches are subequal, of 

 lanceolate shape, and not much longer than the peduncle, the inner one fringed 

 along the inner margin with strong spines and three longer ones distally, and the 

 outer margin fringed with very long feathered seta? ; the outer branch fringed 

 throughout with long feathered seta?, and the outer margin in addition fringed with 

 spines. 



The telson (fig. 21) is short, broad, and of triangular shape, with the apex broadly 

 rounded ; the dorsal surface is convex and the margin fringed with two or more 

 series of stout spines. Compared with Anaspides it is very much shorter. 



Description of a Larval Form. 



I have been able to examine one specimen of a larval form (figs. 22-25). It, measures 

 2 5 mm. in length and its general appearance is like that of an adult. All the 

 appendages of the head and peraeon are well developed, and so also are the terminal 

 pair of the abdomen, but the five preceding pairs are rudimentary. I offer some 

 details concerning it. 



The cephalon has the first thoracic somite joined to it without any distinct mark 

 of division more than a lateral sulcus as in the adult. The front, in dorsal view, is 

 broadly and evenly rounded with the margin entire, the eyes small and situated on 

 the dorsum, and the body-somites all clearly marked off and quite similar in form 

 to the adult. 



The antennules have no difference from those of the adult, except that the joints of 

 the flagella are relatively stouter, longer, and much fewer in number. This is also 

 the case in the antennae (fig. 21), so that there is no apparent difference between the 

 peduncle and flagellum. 



None of the appendages of the buccal area showed any structural differences, and 

 although I suspected that I might be able to determine a spine-row in the mandibles, 

 I failed to do so. 



The first appendage of the peraeon is quite similar to that of the adult, except in 

 having fewer articles in the flagellum of the exopod. The three claws of the dactylus 

 are fully matured. The second and third pairs offer no important differences from the 

 preceding one. The fourth (fig. 25) is also in agreement, except that the dactylus 

 has but one very long claw, and a seta on each side of it, instead of three claws 

 (fig. 25 a). This seems to show that the two lateral claws which exist in the adult, 

 and also in the preceding limbs of this larva, are modified setae ; and this gives some 

 support to Dr. Hansen's view that the terminal claw of the Malacostracan limb 

 represents a separate joint. However, I only know of Hansen's generalization through 



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