74 W. N. F. WOODLAND 



Part II. 



On the Irregular-form Stage of Development in the 

 Life-cycle of Amphilina paragonopora. 



I have already mentioned in Part I that in addition to the 

 active Amphilina paragonopora there are to be found 

 attached to the mesentery and, in the case of the larger bodies, 

 lying free in the body-cavity of Macrones aor and 

 M. seenghala, large numbers of masses of tissue, varying 

 greatly in size and form and, except in the case of the smaller 

 bodies, rarely showing any approach to a definite shape 

 (PL 3, fig. 2), but which, nevertheless, are similar in colour to 

 the active worm, though they differ in consistency, it being 

 impossible to flatten them between glass slides. They are quite 

 distinct from the similarly coloured masses of fat, being denser 

 in appearance and texture. These amorphous ^ masses are 

 stages in the development of the active Amphilina, a fact 

 which is proved by the discovery of stages transitional between 

 the two (vide PI. 3, tig. 2, in, n), and they represent a distinct 

 part of the life-cycle of the species. The portion of life-cycle 

 from the formation and escape of the larva from the fish to 

 the first appearance of the amorphous masses in the mesentery 

 of the fish is unknown. 



The smallest amorphous masses which can be detected in 

 the mesentery by the naked eye are spherical or ovoid in 

 shape (PI. 3, fig. 2, a),^ and there exist all transitions from 

 these small masses up to elongated masses 80 mm. or more 

 in length (Pis. 3, 5, figs. 2 and 46). I have cut serial sections of 

 some dozens of these masses and also through portions of 

 infected mesentery, and by close examination of these I have 



^ I use this term, which strictly spealuiig can only be applied to a gas, 

 for want of a better. So far as I am aware thei'e is no term in use in English 

 to express the meanuig of indefinite shape as apart from delinite. Professor 

 Piatt suggested ' ataxomorphic '. 



'^ It is impossible to distinguish these with the naked eye from the 

 numerous Nematode cysts which also abound. 



