54 W. ©. MCINTOSH. 
methods of microscopic investigation had not been introduced. 
The sections were made from examples of Euphrosyne 
foliosa, Aud. and Ed., and a few from E. cirrata, Sars, a 
northern species, kindly sent by Canon Norman; and I have 
to thank Mr. C. H. Williamson, M.A., B.Sc., for preparing 
and mounting the slides ; and also for aid in this respect from 
Mr. A. T. Masterman, B.A. (Cantab.). 
Body-wall.—The cuticle is of considerable thickness, and 
in the dorsal region and some other parts has externally in 
the preparations a striated granular coat, which may be con- 
nected with the presence of cilia. It is, on the whole, some- 
what thicker than in Spinther. The hypoderm beneath has 
the usual structure, and is very thin in the mid-dorsal line, 
but increases laterally, and again ventrally. The inner edge 
is sharply defined, so as to separate the circular muscular coat 
distinctly, but a definite basement-layer does not appear to be 
formed. Proportionately this layer is somewhat less developed 
than in Spinther. The circular muscular coat lies imme- 
diately beneath the hypoderm in the form of a continuous 
sheath, though in the dorso-lateral regions it is modified; 
the main mass, however, bounding the perivisceral chamber 
and forming a thick ventral layer, pierced here and there 
by the fibres of the vertical and oblique muscles. In the 
lateral regions a radiate arrangement of powerful muscles 
takes place in connection with the bristles; indeed, a double 
radiate arrangement is present in many sections where the 
upper and lower series of bristles come in the way of the 
knife. 
The longitudinal muscular layer forms dorsally a series of fine 
fasciculi beneath the circular, and it follows the latter in its 
course outside the perivisceral chamber, attaining its maximum 
thickness after the splitting of the circular coat. Ventrally 
the powerful longitudinal muscles are grouped in large fasciculi 
separated by the vertical or oblique strands which pass to the 
circular layer. The fibres from the oblique muscles decussate 
beneath the nerve-cords, many mingling with the circular 
(Pl. 7, fig. 4). The latter feature is much less evident in 
