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December 11, 1850. Dr. Arthur Farre, President, in the chair. 

 A paper by P. H. Gosse, Esq., ' On the Notomata parasita, 

 Ehrenb., a rotiferous animal, inhabiting the Spheres of Vol vox glo- 

 bator,' was read. 



After stating that this animalcule was first described by Professor 

 Ehrenberg, in 1835, Mr. Gosse stated that he first observed it on the 

 26th of June, 1850, in specimens of Volvox globator, in water, given 

 him by Alfred Rosling, Esq. He afterwards obtained it from a little 

 pool near the railway-station at Leamington, in Warwickshire. This 

 creature is too small to be seen by the unassisted eye, its greatest 

 length being about a hundred and sixtieth of an inch. The author 

 minutely described the anatomy of this animalcule, and also gave an 

 account of its curious habits, it being parasitic in the elegant Volvox 

 globator, within the globe of which it lives at ease, swimming about 

 like a gold-fish in a glass vase. It appears to subsist upon either the 

 green granules with which the gelatinous surface of the Volvox is 

 studded, or else upon the embryo clusters. It often happens that 

 two or more Notomatoe are seen in the same Volvox, and Mr. Gosse 

 states that in one individual he had met with as many as four, with 

 an egg besides. They are to be found chiefly in the smaller Volvoces, 

 and especially in those which have the embryos in a very immature 

 state. They have also been met with in the embryos themselves 

 when almost grown and nearl}' ready for escape from the parent 

 globe. The operations of this parasite do not appear to occasion 

 any perceptible inconvenience to the containing Volvox. In some 

 spheres eggs are found with Notomata, in others eggs alone. Mr. 

 Gosse also stated his opinion that it was possible that this parasite is 

 always hatched in a parent Volvox, but that the embryonic globe is 

 entered from without. He next described the eggs, some of which 

 are smooth, and others covered with prickles ; and he suggested 

 that, as in these animals the sexes are distinct, both as regards size, 

 form and structure, the smooth eggs might be those of females, and 

 the prickly ones those of males. He concluded with some remarks 

 on the habits of this curious parasite. 



Another paper by G. C. Handford, Esq., ' On a white Mirror for 

 the Microscope,' was also read. 



Wishing to correct the unpleasant glare and other inconveniences 

 attendant on the reflected light of an ordinary silvered glass mirror, 

 the author was induced to construct one by which he considers these 

 defects may be remedied. It consists of a thin, concave glass, three 

 inches in diameter, the back of which is rendered white by means of 



