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the throat and head. The sides of the body were reddish-brown, 

 whilst the middle or dorsal region exhibited a dusky or grayish 

 band, extending from the head to the tip of the tail, and mar- 

 gined with a blackish-brown line, in the midst of which the first 

 series of black spots ran, disappearing, however, upon the tail. 

 The lateral series of spots was not conspicuous, and was only 

 visible distinctly during the act of respiration. 



Prof. Wyman remarked that it had probably been frequently 

 noticed by members of the Society, that, at the present season of 

 the year, the common housefly may be frequently seen hanging 

 dead from the ceiling or attached to any surface on which it may 

 be lying, by a filamentous white substance ; and that a white 

 powder, in greater or less quantity, is frequently seen dotted over 

 the neighboring surface. On examining this substance, he had 

 found the insect to have fallen a victim to a parasitic plant grow- 

 ing upon its surface. The white powder proved to be the spores 

 of the parasite. The whole interior of the fly was found to be 

 filled with a similar plant, and probably, from the diflerent way 

 in which it develops itself, of a different species from that on 

 the surface. The internal parasite starts from a spore, and 

 grows by elongation from one or both sides of a sphere, this 

 latter remaining in the middle or at one end. Prof. Wyman 

 exhibited magnified drawings of these parasites, as they appear 

 under the microscope, in their various stages of development. 



Prof. Wyman also exhibited a dried preparation of the vocal 

 apparatus of the Howling Monkey of South America. This 

 apparatus has before been described, and consists, in the main, 

 of the same parts as in man, with the addition of a new muscle, 

 now for the first time mentioned, and a peculiar structure of the 

 hyoid bone ; the whole apparatus being enormously magnified, 

 and much larger than in man. The muscle not heretofore no- 

 ticed is a Costo-thyroid, outside of the Slerno-thyroid muscle, 

 and entirely distinct from it. 



The President again called the attention of the Society to an 

 inexplicable impression on the Sandstone slab, bearing ripple- 

 marks, which he had exhibited at the previous meeting. He 

 exhibited, in connection with it, several impressions of fossil fish, 



