H. A. Baylis 
371 
of Baird’s original material, which is contained in two bottles in the 
British Museum collection. One bottle is labelled “male,” the other 
“female,” but both now contain examples of both sexes. The contents 
of one bottle are in very poor condition, and I have made use of these 
only as an aid in following out the tail-papillae of the male, which 
happen to be easily seen owing to the macerated condition of the internal 
parts of the worms. The other bottle contains 8 specimens in a very 
fair state of preservation, and some of these have given good results 
when treated with creosote. 
The specimens show several features in which they differ markedly 
from A. decipiens, and I do not think that they can be ascribed to any 
of the other species of A.scaris from seals, of which adequate descriptions 
have been published. Hence I am inclined to uphold Baird’s view that 
this is a distinct species, and to retain his name for it. His description 
and figures, however, are so inadequate, according to modern require¬ 
ments, that it will be advisable to supplement them with a brief new 
description of the material. 
The specimens vary from about 40 to 60 mm. in length, and from 
1 to 2 mm. in thickness. The body tapers much more gradually 
anteriorly than posteriorly, especially in the female. 
The cuticle is divided by transverse grooves into bands about 
23 fi wide, in each of which there are about ten finer striations. 
Contrary to the statement of Baird, there are no prominent lateral 
alae, except in the male, where they are limited to a very small expansion 
at the sides of the tail. The lateral fields, however, which measure 
0-27 mm. in width, are visible to the naked eye as pale bands, and in 
all probability Baird mistook these for “wings.” 
There is a pair of large neck-papillae, situated at about 0-78 mm. 
from the anterior end. 
The lips (PI. XV, fig. 2) have a characteristic shape, and are quite 
different from those of A. decipiens. The dorsal lip is shorter than the 
other two, and is more or less crescentic in outline, with a prominent 
bilobed anterior portion projecting from the middle of its inner, or 
concave, side. The “ pulp ” is prolonged into the horns of the “ crescent,” 
and also sends two rounded processes into the anterior lobe. There is a 
pair of double papillae on the convex surface of the “crescent.” The 
two ventro-lateral lips are of a more usual shape, each having a bilobed 
anterior projection and a large double papilla on the outer surface. 
The two processes of the “pulp” which extend into the anterior pro¬ 
jection of each lip are unequal, that nearer to the mid-ventral line 
