1V PARASITIC CASTRATION IO! 
on the Hermit-crab, Hupagurus excavatus, var. meticulosa.' The 
ordinary males of LZ. mauritanicus have the appearance shown 
in Fig. 72, A. The abdomen is small and bears a pair of 
copulatory styles, while the chelipedes are long and swollen. In 
the female (B) the abdomen is much larger and trough-shaped, 
Fic. 72.—Wlustrating the effect of parasitic Sacculina neglecta on Inachus imauri- 
tanicus, nat. size. A, Normal male ; Jnachws; B, normal female ; C, male infested 
by Sacculina (final stage) ; D, abdomen of infested female ; E, infested male in an 
early stage of its modification. 
and carries four pairs of ovigerous appendages; the chelae are 
small and narrow. 
Now it is found that in about 70 per cent of males infected 
with Sacculina the body takes on to varying degrees the female 
characters, the abdomen becoming broad as in the female, with a 
tendency to develop the ovigerous appendages, while the chelae 
become reduced (Fig. 72, C). This assumption of the female 
characteristics by the male under the influence of the parasite 
may be so perfect that the abdomen and chelae become typically 
female in dimensions, while the abdomen develops not only the 
1. A. Potts, Quart. J. Mer. Sci. Y., 1906, p. 599. 
