146 E. PERRONCITO ON THE ENDEMIC DISEASE OF THE 



first in zigzags, and then straight with the lengthening of the larva. 

 It presents on the anal side, towards the middle part of the body, 

 between the intestine and the mnscular-dermal stratum, an ovoidal 

 corpuscule smaller than in the larvae of the Anchilostoma, evidently 

 the representative of the genital rudiment. The larvae of the 

 Anguillula intestinalis are distinguished from those of the Anchilo- 

 stoma by their different habits and mode of life. Whilst the larvje 

 of the Anchilostoma, before incapsulation, do not live in liquids, 

 i\\o^Q oi ih.Q A ngmllula seem to need them. Substances rather 

 hard put in incubation, after 24 hours, gave a strong contingent of 

 open larvge, which were, however, for the most part dead. This is 

 always revealed, as in the larvae of the Anchilostoma, by a fatty 

 granular degeneration of the tissues constituting the larva, so that 

 the change supposed or described by others for the larvse of the 

 Anchilostoma becomes simulated even in these dead larvsB of the 

 Anguillula. Repeated experiments convinced me of the necessity 

 of changing the mode of cultivation for the Anguilhilce. 



And this method was especially suggested to me from having 

 observed that the larvse of Anguillulce lived capitally in preparations 

 with distilled water, common water, and with dilutions of chloride 

 of soda and sulphate of soda in different degrees of concentration 

 up to 5, 6 and 7 per cent., as will be the better proved by the de- 

 scription of the experiments made thereof. 



If to the substances containing eggs of Anguillula water be 

 added, so that the larv^ as soon as born can swim and freely 

 exercise their serpent-like motion, after 24 hours they may be 

 found of the length of 480yu. So that, supposing the medium 

 length of the newly hatched larva to be 240/z. it grows in one day 

 to double its length. In a very short time they present a trans- 

 formation in their internal organisation. They still maintain the 

 same breadth of 12yLi. and arrive at most to 16yu. on a length of 

 400 to 500/x. Their head becomes rounded, the pharynx and the 

 mouth are completely changed, and are substituted by a granular 

 protoplasmic substance, which supposes the formation of other 

 organs. The internal cavity of the body, for the whole length of 

 the larva to the anus is seen to be granular and compressed be- 

 tween the muscular-dormic structure of the two sides forming the 

 skin. With the transformation of the aUmentary canal, analogously 

 to what succeeds in the larvae of the AncJiilostoma is produced the 

 capsule that encloses and takes the form of the larva. This capsule, 

 observed with my pupil in the laboratory, acting as assistant, Dr. 



