114 G. HERBERT FOWLER. 
[? = mandibles + maxille i] of some complexity; (2) a com- 
plete ring-shaped segment [the true head] from which the 
antenne take origin, and from which grow out the stalks 
which expand into the carapace. [The position of the antenne, 
and of the supra-cesophageal ganglion (1. c., pl. iv, fig. 44) 
seem to leave no doubt that this part corresponds to the true 
head.] Ventrally this [head] bears a pair of [sucker-like] 
swellings, as to the nature of which the French Professor 
expresses himself in doubt; in one place (p. 70), stating that 
they may, “‘morphologiquement peut-étre, représentent quelques 
paires ou pieces buccales ou appendices supérieurs;” at another 
(p. 148), styling them “ antennules, ou tubercles sous-cépha- 
liques.” [Being post-oral and ventral they can hardly be 
regarded as antennules, and may possibly correspond to a 
(second) pair of maxille.] (3) The next region consists of 
six complete [thoracic] segments, each bearing a pair of simple 
uniramose limbs. At the base of the first pair open the 
oviducts; in the bases of the succeeding four pairs lie the 
testes, opening on the basal joint by a number of small 
tubules; the last, or sixth pair, has no connection with 
the generative organs. (4) Behind this [thoracic] region 
come three limbless [abdominal] segments, with the last of 
which articulate a pair of stout caudal spines. In the cara- 
pace lie a strong adductor muscle, and the hepato-pancreatic 
and ovarial ceca, the latter opening as mentioned above at 
the base of the first [thoracic] limb, and connected with each 
other by a bridge above the intestine [as in Petrarca]. The 
cesophagus [stomodzeum] projects on a papilla into the intestine 
(l.c., pl. iv, fig. 44) ; the latter, after giving off a hepato-pan- 
creatic cecum into the carapace on each side, passes to the 
caudal region, where Lacaze-Duthiers was unable to demon- 
strate the presence of an anus. [The nervous system consists 
of the same parts as that of Petrarca described above.] A 
Nauplius, and probably also a Cypris-larva (cf. 1. c., p. 137, 
pl. vii, fig. 102), occur in the development. 
On comparing Petrarca with this description, it is at once 
apparent that the new type has undergone a much greater 
