202 ANCEID®. 
He -also notices “the shortness of the pleon, and the 
smallness and more equal size of the pereiopoda.” The 
three organs on the right-hand side of the above wood- 
cut represent first, to the left, the four-jointed outer foot- 
jaw, of comparatively very small size, the basal joint 
being large and curved, and the apical one very minute. 
The middle, scale-like, exarticulate piece clearly repre- 
sents the scale, which is the homotype of those belonging 
to the incubatory pouch; and the large five-joint organ 
to the right is one of the inner pair of the foot-jaws 
which, in the female of A. mazillaris, is comparatively 
very minute, and which we have failed to discover in 
the female of A. Halidaitii The organ represented on 
the left side of our woodcut is the outer foot-jaw 
seen in a different position, in which the minute apical 
joint is not visible. These specimens were forwarded 
from Banff by Mr. Edward, in whose honour they 
were specifically named. One of them was charged 
with young, and a figure of one of the larve extracted 
from the incubatory pouch is represented in the left- 
hand figure of the woodcut upon p. 177. “It is a 
remarkable fact,” observes the author in introductory 
remarks on the genus, “that in the young the organs 
generally bear a closer resemblance to those of P. c@ru- 
leata than to those of their own parent species.” We 
are now able to account for this remarkable fact, from 
having learned that P. c@ruleata, which we then con- 
sidered as a distinct species in a fully developed con- 
dition, is only a full-grown larva of the preceding 
species, 
Our knowledge of the present species must of course 
be considered as imperfect until its legitimate male is 
discovered. 
