REPORT ON THE SCHIZOPODA. 161 



others, a regular series along the outer edge of the basal part, which appears here 

 a little expanded, thus representing the first rudiment of the lamellar exognath. The 

 terminal joint, or palp, in this stage is now considerably expanded, and assumes a form 

 more in accordance with that of the adult animal, though still provided with only three 

 setge. In the following stages, however, the number of setae gradually increases, and 

 the short spiniform bristles, characteristic of the present species, make their appearance, 

 only a single one being at first developed. 



The Maxillipeds (figs. 19-22). — In the Calyptopis and Furcilia stages these 

 limbs retain their original structure (see fig. 19) almost unchanged, agreeing precisely 

 with that of the larvae of Nyctiphanes, as described above. In the last Furcilia stage, 

 however, a very slight elongation of the endopodite can be traced, and in the first 

 Cyrtopia stage this part (see fig. 20) has become triarticulate, the middle joint being 

 rather elongate and exhibiting a slight trace of a median constriction, whereas the 

 apical joint is very small. In the last Cyrtopia stage the endopodite (see fig. 21) is 

 still more produced and distinctly four-jointed, and, finally, in the first post-larval stage 

 this part (see fig. 22) has become quite pediform and composed of five distinctly 

 defined joints. The exopodite in the same stage shows an incipient division into 

 two principal parts, viz., the basal and terminal, the division, however, being not yet 

 fully complete. 



The Legs (figs. 23-27). — The first trace of these limbs is found in the first Furcilia 

 stage, a pair of small simple processes (fig. 23) then appearing just behind the maxilli- 

 peds. These processes, representing the first pair of legs, rapidly increase and give 

 origin, at their outer side, to a small lateral knob, the first appearance of the exopod 

 (see fig. 24). In the intermediate Furcilia stage, represented in PI. XXIX. fig. 6, the 

 endopod (fig. 25) has already become distinctly articulated and provided with a few 

 small bristles. Moreover, in this stage the luminous globule, imbedded in the coxal 

 joint, is faintly seen, as also the first trace of the corresponding gill. In the last 

 Furcilia stage these legs (fig. 26) are quite pediform, the endopod being rather pro- 

 duced and five-jointed, and in the Cyrtopia stages (fig. 27) they assume more and 

 more the structure characteristic of the adult animal, until, in the first post-larval stage, 

 they merely differ by reason of the somewhat smaller number of marginal bristles. 



The second paii- of legs are found in the intermediate Furcilia stage, budding forth 

 behind the first in precisely the same manner as that pair ; and the following pairs 

 make their appearance successively in the next stages, until, in the first post-larval stage, 

 aU the five pairs present in the adult animal are fully developed, the last, however, 

 being still very small. 



The Gills (figs. 28-32). — As previously stated, the first trace of these organs occurs 

 as early as the intermediate Furcilia stage described above, but merely as incon.spicuous 

 simple knob-like projections at the bases of the Inidding legs (see fig. 25). In the last 



(ZOOL. CHALL. EXP. PART XXXVII. 1885.) Oo 21 



