them when taken from a part nearer the end of the uterus, the disap- 

 pearance of the granules was still more marked, and the form of the 

 future worm could now be made out, (fig. 8) : when arrived at this 

 point of development the young in the interior of the ovum could be 

 traced progressively until they were perfectly formed (fig. 9), and 

 when slight pressure was made on the lower end of the Entozoon the 

 young escaped readily at the uterine aperture, and were quite lively 

 even after the porpoise from which they were taken had been dead a 

 week. The ova were about -fa of an inch in length and very easily 

 ruptured, especially those which contained the young perfectly deve- 

 loped. In every female the transition from the vitelline globules to 

 the perfect worm was to be seen. 



The next species was found in common with the last, being twisted 

 together in a knot around them, both in the bronchial tubes and blood- 

 vessels. It has been noticed as the young of Strongylus injlexus, but 

 on comparing them both together I find that the difference between 

 the two is so marked as to leave no doubt of their being distinct spe- 

 cies ; and I have since been much pleased to find that the same view 

 of the matter was adopted by Kuhn,* who has described it under the 

 name of Strongylus convolutus. 



The females are much larger than the males, and both are much in- 

 ferior in size to the injlexus, the one being about two inches in length 

 and the other about an inch and a half. They are of nearly unifonn 

 diameter throughout, and their black intestinal canal is very visible 

 through their parietes ; in some specimens it took a straight, in others 

 a tortuous course ; the head was more pointed than in the injlexus, 

 and the commencement of the oesophagus was marked with striae, (fig. 

 10). Nothing remarkable was observed in any other part of the body 

 except the tail, which was slightly flattened, and on one side only 

 was provided with a membrane which was continuous with a small 

 semicircular terminal portion, in which were placed three very small 

 horn-like bodies, arranged in a radiated form ; in the lower part of 

 the worm two dark curved bodies were placed parallel to each other, 

 which were probably connected with the genital apparatus, (fig. 11 a). 

 In the female the genital apparatus was double, as in the last species, 

 but was quite free from the contractions and dilatations ; its contents, 

 like those of the injlexus, exhibited the gradual transition from vitel- 

 line globules to the perfect worm, but in many specimens the disap- 

 pearance of the globules commenced in the centre, and so went on 



* Memoircs du Museum d'Histoire Naturelle, tome xviii. p. iif)7. 



