IN THE GENUS SQUALUS, 
165 
they gave off numerous minute filaments that pierced the 
great sac, and terminated on the inside in a remarkable 
substance. This substance is the same in both modes of 
distribution; and, from the gritty sensation that is felt 
when rubbing part of the substance between the finger 
and thumb, it may be termed the Sabulous Body. This 
remarkable substance occupies the posterior, inferior, and 
inner parts of the sac ; is of an oblong figure, sometimes 
partially concave, but generally with an irregular surface 
in the adult, and terminates in a horn-like process that 
shoots downwards, and a little forwards, and sometimes 
slightly inwards, and which, from its resemblance to the 
horn of the ram of Angora, may be termed the Cornu 
Angorianum. The body of this substance (independent 
of the process) measures from six to eight lines in length, 
four in breadth, and from two to three lines in thickness. 
These measurements vary according to the age and size 
of the subject. 
In the very young fish of the species Squalus Caninus, the 
whole of the substance is of a dark blue colour ; but, as the 
animal grows older, it changes to that of a light grey. 
I have seen it sometimes in the young fish, coloured so 
as. to appear to consist of three divisions ; the upper divi- 
sion of a dark blue colour, intermingled with a few hghter 
particles. The middle and largest of the divisions of a 
cream colour, with a few dark particles ; and the division 
next to the plexus, which formed only one-third of the ex- 
tent of either of the other divisions, composed of white par- 
ticles. 
In the large shark, and several species of young skate, 
the particles are white, and consequently finer in the latter 
than in the former, where they are seldom found of that 
colour, except in the adult. Hence the opinion of several 
anatomists, that these bodies are chalky concretions. It 
