CRUSTACEA OF THE MERGUI ARCHIPELAGO. 295 
presents an oblique notch and another slight emargination is 
observed near the proximal end of the outer margin of the 
external urorami. A similar structure is proper to the male of 
Peneus affinis, M.-Edw., according to Spence Bate (J. c. p. 179, 
pl. xu. fig. 6v). In the urorami of the female these notches are 
quite wanting. 
The “ventral plate’ of the female lying between the last two 
pairs of legs, strange to say, presents a different shape in the two 
forms of females; in the females A, in which the ischium-joint of 
_ the last pair of legs is triangularly dilated, the ventral plate is 
divided by three grooves, which meet one another in the centre, 
into three multangular smaller plates, a median anterior one and 
two lateral posterior ones. In the two other females, B, the 
ventral plate is not divided into secondary plates, the radiating 
erooves not being found in it. 
This species is 60-70 millim. long from the tip of the rostrum 
to the end of the terminal postabdominal segment. 
Peneus Lysianassa differs from Peneus brevicornis, M.-Edw., 
by its much shorter rostrum, by the longer flagella of the 
internal antenne, and by many other characters, such as the form 
of the petasma, &e. 
The Japanese Peneus lamellatus, de Haan, of which I have 
seen a type specimen from the Leyden Collection, is a quite 
different species, which may be recognized at first sight by its 
larger rostrum, armed with more numerous teeth, by its telson 
being spiniferous along its lateral margins, by the form of its 
petasma, Kc. 
Order STOMATOPODA. 
Genus Squitia, Dana. 
162. SquinLa NEPA, Latr. 
Squilla nepa, Latreille, Encyclop. Méthodique, x. p. 471; Milne- 
Edwards, Hist. Nat. Crustacés, t. ui. p. 522. 
Squilla oratoria, de Haan, Fauna Jap., Crustacea, p. 223, pl. Ix. fig. 2. 
Squilla nepa, Miers, On the Squillide, Ann. § Mag. Nat. List. 
Jan. 1880, p. 25, pl. i. fig. 13. 
One specimen was collected in King Island Bay. 
Some time ago, while in Leyden, J was able to compare a 
typical specimen of Sguwilla levis, Hess, presented to the 
