56 
At least with regard to the structure of the pupe we know, Spheronella Argisse, 
Spher. insignis and Choniostoma mirabile come rather close to the two preceding species ; 
each of them will now be treated separately. 
Spheronella Argisse. Of this species I have found a single female pupa (pl. TV 
fig. 31 and fig. 3m), which in the most important features agrees with the female pupa of 
S. Giardii. The body is ovate, naked all over, -15 mm. in length, and, like the last-men- 
tioned species, provided with the pouch-like processes, in which antennule (a), antenne (c), 
maxillule (e) maxilla (f) maxillipeds (g), trunk-legs and caudal stylets (p) are developed, and 
all these processes show about the same relative size as the corresponding organs in the 
females compared with each other; moreover, the mouth is distinct, and the mandibles are 
also seen in fig. 31. The animal is attached by a very peculiar crooked funnel of conside- 
rable size (s), which is of course made of a viscous substance, and its narrower, though 
comparatively thick, base proceeds from the front. 
Spheronella insignis. Of Diastylis cornuta Boeck a single pupa was found (pl. X, 
fig. 1h), 14 mm. in length and sub-globular in shape. The mouth is well developed, as in 
an adult female; antennule, maxillule, maxilla and maxillipeds are seen as protruding naked 
pouches of somewhat irregular shape; in front of the mouth are found two rather large, odd, 
connected areas, and close behind them a smaller spot on each side of the median line; in 
front of, and in an oblique direction from, the maxillule, there are several small areas, and 
finally a large transverse area, expanded in the middle, which joins the bases of the maxilli- 
peds. All these areas are naked, and more or less prominent compared with the surroun- 
ding skin. Except these organs and areas and the surface between them, the whole ventral 
surface of the pupa and its sides are covered with hairs of medium length; the back is 
covered in the same way on its most anterior part and on its posterior half, whereas a broad, 
transverse area extends over the larger part of its anterior half; this area is naked, and 
closely covered all over with irregular projections of a comparatively rather considerable 
size, the real shape of which can only be recognised when seen obliquely, whereas a perpen- 
dicular view gives the impression that this surface is covered with numerous irregular lines, 
forming ovals, oblong spots or simply flourishes. I have been unable to find out with 
certainty the sex of this interesting pupa, as the adult male of this species is devoid of 
trunk-legs; however, I consider it to be a female. 
Choniostoma mirabile. On the gills of a Hippolyte Gaimardii M.-Edw. 1 have 
found a number af larve, which showed all the stages transitional to that of the pupa, 
besides numerous fully developed pup (pl. XI, fig. 1 g—1k). A comparison between the 
figures 1h, 1i og 1k, which are drawn to the same scale of enlargement, will show that 
the pup differ much in size and somewhat in shape; the largest specimen I have measured 
is 38 mm. broad and -27 mm. long, the smallest only ‘27 mm. broad and °19 mm. long, 
and one specimen, which was still enclosed in the skin of the larva, is only “19 mm. broad 
and ‘18 mm. long. So the pupe grow very considerably after breaking out of the larval 
