1883.] 



MICROSCOPICAL JOURNAL. 



39 



F. Atwood alluded to some of the ento- 

 mostraca in the water of Hemlock Lake 

 as follows : — 



The attention of the members is called 

 to the number of Cant/iocai/iplus ininii- 

 tus, now in the water of Hemlock Lake. 

 While I have occasionally noticed them 

 in filterings of our water-supply, they 

 have never seemed so plenty as during 

 the last week or two. In a filtering made 

 yesterday they constituted the bulk of my 

 find. The CaiitJiocainptus i/iiiaUi/s is, to 

 my mind, one of the most beautiful and 

 interesting of the entomostraca. Smaller 

 than the Cyclops, and much more trimly 

 built, it has the same number of segments 

 in the body, but, unlike the Cyclops, 

 there is no clearly-defined division be- 

 tween the thorax and abdomen, there 

 being a gradual taper from the head to 

 the posterior segment. From the latter 

 two long and two short bristles project, 

 the former, in many instances, being as 

 long as the entire animal. The antennas 

 are much shorter than in Cyclops or 

 Diaptomi, consisting of only seven seg- 

 ments or articulations in the male, and 

 nine in the female. The females, at this 

 time of the year, carry a single sac full of 

 eggs, which are quite embryonic as yet. 

 In February we will have ample oppor- 

 tunity to study the young. 



At a meeting of the New York Soci- 

 ety, held February 2d, a paper was read 

 on " Correction-Adjustment for Homo- 

 geneous Immersion Objectives," which 

 is published in another column. Mr. C. 

 Van Brunt then spoke a few words about 

 Amphipleiira pellucida. He stated that 

 he had recently visited Geneva, where he 

 saw the A. pellucida resolved by Mr. 

 Spencer with an unfinished J^-objective, 

 a flour-barrel being used for a table, and 

 the mirror-bar of the microscope being so 

 loose that it had to be propped up with a 

 stick. Daylight was used for illumina- 

 tion, and the Hues were remarkably dis- 

 tinct throughout the length of the frustule. 

 Mr. Spencer and Prof. Hamilton Smith 

 both seem to think the new lens will, 

 when completed, surpass anything yet 

 constructed for resolutions. The lens 

 will soon be the property of the speaker. 

 Prof. Smith has been cultivating ^.^^Z- 

 lucida in a vial, and the diatoms grow 

 vigorously, and collect upon the sides of 

 the vial away from the light. 



The entire frustule was represented on 

 the black-board as it appears under the 

 microscope, showing the outline of the 

 valve and the two raphes, but no line in- 



dicating the hne of junction between the 

 two valves can be seen. Owing to the 

 absence of such a line, it has been 

 thought the cross section of the frustule 

 must be triangular — the diatom being 

 composed of three valves. 



The speaker alluded to the great diffi- 

 culty of removing air from certain dia- 

 toms, such as the IstJunia and others. 

 He has found the following method to 

 succeed perfectly well: The frustules are 

 dried on the cover-glass, which is then 

 placed on a slide, diatoms up, and plain 

 balsam is dropped upon them. By heat 

 the balsam is caused to flow around the 

 diatoms, but it does not replace all the 

 air within them. By alternately heating 

 the balsam up to the boiling point and 

 then cooling it, two or three times, all the 

 air can be expelled. 



President Bi-aman made a few remarks 

 about the structure of diatoms, and their 

 classification. 



Mr. Balen showed some fine specimens 

 of pond-hfe, including some of the flagel- 

 late infusoria. He mentioned particularly 

 some of the family Astasiaea, and said 

 they seemed to differ from Englenae only 

 in the absence of color. Mr. Hyatt re- 

 ferred to his obervations on the change 

 of color of the Englenas from bright- 

 green to a brilliant red. 



Mr. Britton called attention to a de- 

 posit of diatoms recently discovered on 

 Staten Island, at Clove Lake, and ex- 

 hibited a specimen. Mr. Van Brunt iden- 

 tified one of the forms as Siepliaiiodiscus. 



Mr. Mead showed two slides of Bacil- 

 lus tuberculosis, prepared by Ehrlich's 

 method, one of which had been treated 

 with ether to remove any fatty matter 

 that might be present. 



NOTICES OF BOOKS. 



The A'aturalisf s Assistant : A Handbook 

 for the Collector and Student. With a 

 Bibliography of fifteen hundred works 

 necessary for the systematic zoologist. 

 By J. S. Kingsley, Boston : S. E. Cas- 

 sino, Publisher, 1882. (Small 8vo., pp. 

 228. Price $1.50.) 



This is a book of which we can well 

 appreciate the value, since it is just such 

 a work as we have felt the need of in col- 

 lecting. We can recall many an interest- 

 ing specimen which we would have been 

 glad to preserve, had we known the proper 



