ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 107 



a paper on " The British Spiders of the genus LijcosaT Mr. F. P. 

 Smith delivered a lecture on "Vagabond Spiders." He said that by 

 " vagabond " he meant " wandering," and included in the term all those 

 spiders which did not make snares. The three principal groups of 

 " vagabonds " were represented by the families Lycosidae, Thomisid^e, 

 and Salticidae, and their characteristics were described at some length. 



At the 435th Ordinary Meeting, held on December 21, 1906, Mr. 

 W. R. Traviss exhibited and described an expanding central stop for 

 obtaining dark-ground illumination. A " Note on New Diatom Struc- 

 ture," by Mr. a! C. Eliot MarUn, F.R.M.S., was read. This dealt with 

 " veiled " markings recently noted on certain species of Melosira and 

 Hyalodisciis, and on a Navicula and Avlodisms. Details of apparatus 

 employed and illumination used were given. An interesting discussion 

 followed. 



Behn, N., & W. Heuse — Zur Demonstration der Abbeschen Theorie des Mikro- 

 skops. Verh. d. Phijs. Ges., viii. (1906) pp. 283-9. 



Day, a. L., & E. S. Shepherd — Quarzglas. 



Deutsch. Median. Zeit., 1906, p. 137. See also Scieiice, 



xxiii. (1906) p. 670. 



B. Technique.* 

 (1) Collecting- Objects, including- Culture Processes. 



Artificial Cultivation of Spirochseta pallida.! — A. Fontana re- 

 moved small portions of tissue from primary sores and soft papilla, and 

 introduced them into various fluid media — sterile human blood, human 

 blood with citrate of sodium solution, blood serum, ascitic fluid, etc. ; 

 most of the tubes became overgrown with contaminating organisms by 

 the fortieth day, but in no case was there any cultural development of 

 spirochsetes. But examination of the portions of tissue showed that the 

 spirochetes were still present, having withstood the action of the other 

 organisms ; and those portions that were kept at 37° C. from 8-30 days 

 showed a great increase in the number of the spirochetes : and this was 

 especially the case when the portions of tissue were brought into ascitic 

 fluid and into gelatin with ascitic fluid and incubated at 37° C. 



By placing portions of skin or mucous membrane from non-syphilitic 

 individuals in the test glasses, together with portions of syphilitic tissue, 

 the authors demonstrated in several cases the transference of spirochetes 

 from the diseased into the healthy tissue. 



Direct Impression on Photographic Paper to Replace Drawings 

 by Hand.J — M. Yegounow by the use of Velox paper obtains good 

 shadow images, for which he details many obvious uses and advantages 

 over drawings made by hand, especially in representing cultures on Petri 

 dishes, ascertaining the contours of small objects, and acquiring measure- 

 ments of colonies. 



* This subdivision contains (1) Collecting Objects, including Culture Pro- 

 cesses; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes ; 

 (4) Staining and Injecting ; (5) Mounting, including slides, preservative fluids, etc. ; 

 (6) ^Miscellaneous. 



t Centralbl. Bakt., 1^ Abt Orig. xlii. (1906) p. 666. 



t Op. cit., 2te Abt. xvii. (1906) p. 412. 



