52 The Microscope. 



prepared by the famous Amici, fifty years ago, also some slides 

 which he himself prepared. He showed a Rogers ruling on gold of 

 the standard inch, a Rogers ruling on steel of the standard 

 decimeter, a Fasoldts ruling of 120,000 lines to the inch. A 

 Roberts ruling, including the famous 19th band. From his histolo- 

 gical collection mounted by Prof. Theirsch, some of the most notable 

 among those exhibited where the ovarium of a pheasant entire, the 

 section of a human kidney entire, section of a portion of human 

 brain, and the iris and choroid of the eye of a kid mounted on con- 

 cave slides, the entire respiratory system of the hydrophillum. This 

 last reminded one of the marvelous tubular bridges of later times. 

 There were also among the exhibits a 500 diatom plate and a 100 

 diatom plate of Miiller. Dr. West at the request of the Society, 

 spoke a few words of his forty years' experience with the microscope, 

 describing some remarkable microscopes of the early, awkward 

 patterns in his possession. Some were specially favored to see a 

 1.50 objective of Tolles, a consummate work of skill. The evening 

 was one which will ever be in the grateful remembrance of the 

 Societ)'. 



The regular monthly meeting of the College Microscopical 

 society took place Saturday, Dec. 4. The President, Miss Ada Wing, 

 was in the chair. After reading of the minutes, certain plans for 

 the future were suggested by Miss Whiting, and adopted by the 

 society. The papers of the evening were upon the "Embryology of 

 the Chick" by Miss Rose Howe, and upon "Recent Studies of 

 Marine Forms" by Miss Barrows. The subject of embryology, so 

 difficult of presentation, was given in a concise, clear and intei'esting 

 manner. By diagrams, Miss Howe showed the structure of an ovum, 

 and the following early stages in its development: 



(a.) Segmentation of the ovum. 



(6.) The germinal layers. 



(c.) The derivation from these thin layers of the most import- 

 ant organs of the adult form. 



Slides were exhibited showing transverse sections of neural 

 canal, notochord, cerebral vesicles, alimentary canal, heart, and 

 organs of sight and hearing. An egg in the fom'th day of develop- 

 ment was opened, revealing beating heart, arteries and veins and 

 vascular area, gradually enclosing the yolk. Miss Barrows spoke of 

 her summer studies at Annisquam, Mass., and described the habitats, 

 habits and structure of a few of the forms there seen. 



Preserved specimens, and the fine collection of glass models in 

 the Zoological museum aided her in making evident to the audience 



