W. Nicoll 
353 
Large specimens have a rich yellowish-brown colour, due largely but 
not entirely to the numerous ova. Young ones are almost colourless. 
The whole body is covered with scale-like spines, most densely set 
anteriorly. The rhynchus is of very large size. In outline it is wedge- 
shaped, the apex of the wedge penetrating deeply into the body, and 
the base, forming the anterior end of the animal, being rounded and 
expanded. In certain cases the apex of the wedge is twisted, giving 
the rhynchus the “cornucopia” shape described by Molin. Frequently, 
especially in young specimens, the rhynchus forms a protruding button¬ 
like structure. Under normal circumstances the edge of the expanded 
anterior end is drawn out somewhat to form a projecting ridge, 
completely encircling the rhynchus. This is only well seen when the 
animal is alive. In a 3T5 mm. specimen the dimensions of the 
rhynchus are 0 - 62 x 057 mm. The histological structure closely 
resembles that of Prosorhynchus squamatus as described by Odhner. 
The mouth is situated almost exactly in the centre of the body. 
The pharynx is circular and measures 0 21 mm. in diameter. The 
intestine extends forwards for a distance of about 03 mm. from the 
pharynx. It is an ovoid or globular sac, connected with the pharynx by 
a narrower portion. The excretory vesicle is comparatively short, 
extending forward about a third of the body length from the posterior 
end, i.e. to the level of the right testis. 
The position of the genital glands is a feature on which no two 
descriptions agree. Molin places the testes symmetrically midway 
behind the pharynx and the ovary in front of the left testis. Olsson 
was able to see only two of the glands, one on each side of the pharynx 
and almost on the same level. In all probability the one on the right 
was the ovary. According to Odhner they have the same relative 
positions as in P. squamatus. I have found specimens corresponding with 
those described by Olsson and Odhner but never one in which the 
ovary was on the left side. Molin’s drawing, however, was almost 
certainly made from the dorsal surface. The species, in respect of the 
genital glands, is by far the most variable which I have ever examined. 
No two specimens are absolutely alike and it is difficult on that account 
to indicate what may be considered the normal or typical structure. 
From my specimens it would appear that the condition more nearly 
approaches that in P. aculeatus than in P. squamatus, in so far as the testes 
are much more frequently placed across the body than one behind the 
other. In every case they are behind the pharynx, but nearer it than 
the posterior end of the body. In the majority they are placed one 
