1888.] MICKOSCOPICAL JOURNAL. 115 



NOTES. 



Postal Microscopical Club. — The 13th annual report of this organization has just 

 been received, and shows a prosperous condition of affairs. The society suffered con- 

 siderable inconvenience from the postal regulation regarding advertisements printed 

 with addresses, under which law the addresses of the boxes were supposed to fall. In 

 spite of this and other difficulties, however, the Club has prospered and done its usual 

 amount of good work, by circulating many most excellent slides and descriptions. Ex- 

 tracts from the note-books furnish many useful hints for practical use. 



Palmer Slide Co. — We have received, recently, from this now well-known optical 

 company, some samples of their slides and some of the mounts by Dr. Reeves, and 

 the crystals by Mr. Bolton. Dr. Reeves is recognized as one of the best preparators 

 in America, and his work is excellent. The Company advertises to furnish all man- 

 ner of microscopical goods at very reasonable prices. Its present address is Cleve- 

 land, Ohio, instead of Geneva, N. Y., as formerly. 



Davenport Academy of Natural Sciences. — The annual meeting was held January 

 4, 1888. The Secretary's report showed that seventeen meetings had been held, with 

 an average attendance of fifteen. Seven regular and five corresponding members had 

 been elected, making a total gain of twelve during the year. Three life members, one 

 regular member, and one corresponding member had died, making a total loss of five. 

 Present membership: — Life membei'S, ']'] \ regular members, 120. 



Papers of scientific value read before the Academy : — Bibliography of Iowa Antiqui- 

 ties, Report on Thunder-Storms of Iowa, Fishes of the Ozark Mountains, Annotated 

 List of the Birds of Iowa, Anglo-Saxon and Latin Words. 



Subjects of more or less general interest discussed : — Clouds, How Sustained in the 

 Atmosphere ; Theories of Thunder and Lightning, The Stone Circles on Dakota Plains, 

 English Sparrows, Theory of Color, Changes in Animal Life Caused by Salt or Fresh 

 Water, Edison's Pyro-Magnetic Generator. 



Lectures: — ' The Vertebral System in Man and Animals,' and a costume lecture 

 under the auspices of the Academy, ' The Indians of Iowa.' 



The Librarian reported additions to the number of 2,025, among them transactions 

 of 250 societies, the National and State publications. 



In the museum the accessions comprise about three hundred vessels of ancient mound 

 pottery, two hundred flint and stone implements, eleven human crania from mounds, 

 one carved stone Indian pipe, two hundred and thirty-five old-time relics from New 

 England, an old electrical machine, twenty-five species of fossils, several hundred spe- 

 cies of recent shells. The collection of recent shells, which has been very largely in- 

 creased by the labors of Mr. Harry A. Pilsbry, includes about twenty-five hundred 

 species. A considerable number of the local species of fishes and reptiles has been 

 collected and preserved. 



MICROSCOPICAL SOCIETIES. 



Essex County, N. J. — F. Vanderpoel, Secy. 



December i , i88j. — Dr. R. R. Andrews, of Cambridge, Mass., spoke upon tooth de- 

 velopment, and exhibited by lantern forty photomicrographs illustrative of his subject. 

 Many of these he had made with an immersion ^V and a ^y> objective. He considered 

 all the stages of tooth development, but especially the formation of the dentine. His 

 conclusions differ from the views of other investigators, and may be briefly stated as 

 follows : — In the formation of dentine there are two varieties of cells called into action. 

 The odontoblast, a cell which is flat and abrupt against the forming dentine, and the 

 fibril-forniing cell, which is pear-shaped, the odontoblast forming the basis substance 

 of the dentine only, and the pear-shaped fibril cell forming the fibril of tomes. The 

 fibril cell has a higher vital function than the odontoblast ; that is, it supplies the nour- 

 ishment to the basis substance. He described his method of preparing the specimens, 

 which varies considerably from those of most investigators, as follows : — ' I take the 

 forming teeth from the jaws of embryos at, or nearly, the time of bii'th, while the tissue 

 is still warm. These are placed in a quarter of one per cent, to one-half of one per 

 cent, solution of chromic acid, which is changed daily for three or four days. At the 

 end of this time the edges of the dentine that were calcified are found to be sufficientlv 



