108 
THE VOYAGE OE H.M.S. CHALLENGES. 
numerous marginal spines, there is little doubt that they are Lysiosquilla, pretty closely 
related to the two which have been described. One of these, an Erichthus 14 mm. long, 
from Beugal, 1 he himself refers to the subgenus Coronis, and his Squillerichthus 
triangularis (fig. 13) and possibly his Erichthus latreillei (fig. 18) are closely related 
species. 
The Challenger collection contains many specimens of a number of species of this 
larval type, some of them very broad and short, and others as narrow as a Gonodactylus 
Erichthus, from which they are distinguished by the position of the- postero-lateral spine 
of the carapace, which is either on the ventral edge or nearer to it than to the dorsal 
middle line, while the reverse is the case in the Gonodactylus larva, which also has its 
hind body convex instead of flat. 
One of these Lysioerichthus larvae from a surface collection made by the Chal- 
lenger at Papua, Japan, is shown in PL XI. figs. 10, 11, 12, and 13. It is T 9 y of an 
inch long on the middle line, with a minute dorsal spine, a rostrum which is nearly as 
long as the carapace, small antero-laterals, and postero-laterals which spring from the 
carapace close to its ventral edge, and reach backwards as far as the middle of the 
sixth abdominal somite, while all the abdominal somites except the first are exposed 
on the middle line. The raptorial claw (fig. 13) is flat, broad and oval, and its 
dactylus shows under the cuticle traces of eight marginal spines. The hind body is 
as wide as the carapace, and the telson (fig. 11) is much wider than long, with 
its posterior border angulated and fringed with numerous small spinules between 
the submedians, the distance between which is about half the greatest width of the 
telson. There is a small spinule internal to the base of each lateral and each inter- 
mediate marginal spine, and one small secondary spine between the intermediate and 
submedian. 
Length of carapace including rostrum, 
Length of exposed somites and telson, 
■48 inch. 
•42 „ 
Total length on middle line, 
Length of postero-lateral spines, 
•90 
•26 
The oval shape of the flattened carpus indicates that this larva is a Coronis. There 
is a general resemblance between it and the one last described, but the raptorial 
claw is less oval, and in a third closely related larva, collected between Sydney and 
Wellington, the raptorial claw is still more elongated. This latter larva, which is shown 
in PI. IX. figs. 6, 7, 8, 9, and 10, is so similar to the one shown in Claus’s figure 20, 
that they must represent related adults, and I am therefore compelled to dispute his 
identification of his larva as a young Gonodactylus. 
It is remarkable for the great length of the rostrum and postero-lateral spines, the 
1 Metamorphose der Squilltden, fig. 19. 
