152 Microscopical Society. 



from the common Porpoise. The author stated, that the subjects of 

 his paper were, with one exception, all found in the lungs of the Por- 

 poise. Two of them had been long known, and had been described 

 by Rudolphi and many others under the names of the Strongylus in- 

 flexus and minor ; whilst a third, from the circumstance of its being 

 found with the inflexus, had, by all others except Kuhn, been described 

 as a younger specimen of that species, but by him as the Strongylus 

 convolutus ; whilst the fourth appeared hitherto either to have escaped 

 notice, or else to have been confounded with the last ; but his exa- 

 minations of this Entozoon led him to consider it as a distinct spe- 

 cies, and from the circumstance of its being inclosed in a sheath or 

 case, he had named it the Strongylus invaginatus, at the suggestion 

 of his friend Dr. Willis. The Strongylus inflexus was the largest of 

 the Entozoa, and it occurred most abundantly in the bronchial tubes, 

 and in such numbers as almost to close them up ; but many speci- 

 mens were found in the right auricle and ventricle of the heart, and 

 in the principal blood-vessels of the lungs as well. The average 

 length of the male is about seven inches, whilst that of the female is 

 nine inches. 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 the in- 

 flexus, but, on comparison, the author finds that the difference be- 

 tween the two is so marked as to leave no doubt of their being di- 

 stinct species : Kuhn has named it the Strongylus convolutus. The 

 third species is the smallest of the whole, some specimens not much 

 exceeding an inch in length, and from this circumstance has been 

 named the Strongylus minor. It occurred in the venous sinuses of 

 the head and in the cavity of the tympanum, and some of them were 

 of a reddish hue, probably owing to their living in blood. The fourth 

 species, the Strongylus invaginatus, was found in small cysts in the 

 lungs not connected with the blood-vessels, to the number of five or 

 six in each cyst, which were easily extracted when the cyst was 

 opened : the male was very much shorter than the female, and both 

 were inclosed in a transparent sheath or case, which was in contact 

 with the body of the worm only at the head and tail. 



After describing the anatomy of each species, the author then pro- 

 ceeded to some interesting peculiarities connected with their ova, in 

 which the gradual transition from vitelline globules to the perfect 

 worm was beautifully seen. He then alluded to the curious fact of 

 the Strongylus inflexus and convolutus living in blood and in air, and 

 concluded with mentioning some other interesting points connected 

 with these Entozoa, and the probable effects they produced in the 

 ceconomy of the animal. The paper was accompanied with draw- 

 ings and illustrative diagrams. 



Mr. Ross exhibited to the Society a new form of the Microscope, 

 in which strength, durability, steadiness, and cheapness were com- 

 bined ; it was capable of exhibiting the usual test-objects, and the 

 price only 12/. 



