REPORT OX THE STOMATOPODA. 
99 
The Lysioerichthus larva, and the Metamorphosis of Lysiosquilla. 
If my decision that all the Alima, larvae are young Squill & be correct, we must look 
for the larvae of all the other genera of Stomatopoda among the Erichthi and 
Squill erichthi ; or, as Squillerichthus is simply an advanced Erichthus, among the 
Erichthi. 
The series of Erichthus larvae is so complete, and transitional forms are so 
numerous, that it is very difficult to divide the group into minor groups ; and while it is 
obvious that there are several distinct larval types, they are so intimately united by 
intermediate forms that the attempt to study them is very puzzling. The genera 
merge into each other in such a way that it is difficult to find any strictly diagnostic 
characteristics, but this is no more than we should expect from the absence of sharply 
limited genera among the adult Stomatopoda. 
I have shown that the species of Lysiosquilla, in which genus I include Coronis, 
and the species of Squilla including Chloridella, exhibit proofs of divergent descent 
from a common stem form, which was more like Coronis and Chloridella than it was 
like the more divergent Lysiosquilla} and Squilla} ; and as I have also shown that the 
larvae of all the species in the Squilla-bianch. from this common stem are Alimae, we 
naturally turn to the AlimoAdke Erichthi in our search for the larval type of the second 
or Lysiosquilla- branch. 
In addition to their features of relationship to the adult genus Squilla, the Alima 
larvae agree with each other in the general occurrence of marginal spines on the lateral 
edges of the carapace, the length of the telson, which is almost always greater than its 
breadth, the flatness of the hind body and the presence of marginal spines on the inner 
edge of the dactylus of the raptorial claw. Squilla and Lysiosquilla agree with each 
other in the flatness of the hind body, and in the presence of spines on the dactylus, but 
the Alima larva shows its relationship to Squilla by the presence of numerous 
secondary spines between the submedian and intermediate marginal spines of the telson, 
by the small number of spines on its dactylus, and by the fact that the inner spine of 
the uropod is always longer than the outer. 
Now there is a group of Erichthus larvae, of which Erichthus duvaucellei (Lysiosquilla 
maculata ?) (PI. X. fig. 7), and Erichthus multispinosus (Lysiosquilla excavatrix) (PI. XI. 
figs. 1, 2 and 3) are examples, which show by the flatness of the hind body, and by the 
presence under the cuticle of the dactylus, in the older larvae, of traces of marginal spines, 
that they are either Squilla or Lysiosquilla larvae. Claus refers them to the genus 
Squilla, but as the marginal spines are usually more numerous than they are in any 
known Squilla or in the Alima larva, we must exclude the genus Squilla in our attempt 
to trace them to their adult form. In some of these larvae there are as many as seventeen 
of these rudimentary spines on the dactylus, and they are seldom less than six, and there 
