ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 445 



reminding one of Actinomyces. These resemble the tubercular bacilli in 

 their behaviour towards reagents, and in their pathogenic properties. 



The following species are then described: — (1) A. glaucus Mich.; (2) 



A. flavus Bref. ; developes involution- forms ; A. Oryzae is probably only a 

 variety ; (3) A. fumigaius Fres. ; the involution-form causes maladies of 

 the lungs and kidneys ; (4) A. clavatus Desm. ; not pathogenic ; (5) A. 

 niger van Tiegh. ; pathogenic, causing diseases of the skin and breasts, but 

 no internal mycosis ; (Q) A. subfuscus n. sp. ; found within putrescent 

 organic bodies, producing in living animals a general mycosis ; (7) A. alhus 

 Wilh. 



Development of Gymnosporangium.*— According to Prof. W. G. 



Farlow, the identity has now been established of Gymnosporangium claviceps 

 (on Juniperus virginiana) with Boestelia aurantiaca (on Amehnchier cana- 

 densis)^ of G. clavariseforme (on J. communis) with B. lacerata (on Gratsegus 

 tomentosa), of G. conicum with B. cornuta, and of G. hiseptatum. with 



B. botryapithes. G. clavipes occurs also on J. communis. Prof. Farlow 

 also believes G. Ellisii to be a form of B. transformans, and G. macropus of 

 B. penicillata. 



Gymnosporangia and their Rcestelise.f — Mr. E. Thaxter, following 

 up Prof. Farlow's paper, communicates the results of further studies 

 on Gymnosporangia or cedar-apples and their relation to Bcestelise. The 

 cycle of development in these fungi is first summarized, and a detailed 

 account is given of the experiments by which the life-history was traced. 

 An attempt is then made to elucidate the difficult problem of the relation 

 of the various species of Gymnosporangium to their respective Bcestelise. 

 The cycle verified by Mr. Thaxter was as follows : — At maturity, towards 

 the close of spring, the cedar-apple consists of sporiferous masses grow- 

 ing from the distortions caused by the mycelium on the stem or leaves of 

 the host. When moistened the masses expand and soften; the spores 

 germinate and form hyphae (promycelia) ; these form secondary spores or 

 sporidia ; these are carried by the wind from the juniper, cypress, &c., to 

 certain Pomefe, where they form Boesteliee. On the new host the sporidia 

 germinate, entering the tissues and causing discoloration. Flask-shaped 

 cavities (spermogonia) appear on the surface, and within these are formed 

 minute bodies or spermatia of doubtful function. Opposite these, on the 

 under side of the leaves, or in the same position with them in young 

 shoots or fruits, cup-shaped secidia are formed, and within these successive 

 sets of spores surrounded by the membranous capsule or peridium. On 

 the rupture of this the liberated spores are carried by the wind to cedars 

 where they reproduce cedar-apples. No definite results were obtained for 

 or against the theory that the S2>ermatia are sexual and fertilize a female 

 " trichogyne " which gives rise subsequently to the secidium. 



New Pythium.| — Under the name PytMum anguillulee aceti, Prof. E. 

 Sadebeck describes a new species which attacks the vinegar-eel, kills it in 

 a short time, and then developes luxuriantly in its dead body. In diifers 

 in no essential respect from the other species of the genus. The conidia 

 and oogones are, however, produced contiguously and at nearly the same 

 time, and the number of conidia is very large ; they usually germinate 

 directly, without the production of zoospores ; the oogones and conidia are 

 smaller than in other species of PytMum. 



* Bot. Gazette, xi. (1886) p. 234. Of. this Journal, 1881, p. 77i. 

 t Amer. Acad, of Arts and Sci., Dec. 1886. Cf, Centralbl. f, Bacteriol. u. Para- 

 sitenkunde, i. (1887) pp. 429-34. 



X SB. Gesell. Bot. Hamburg, Feb, 25, 1886. See Bot. Centralbl., xxix. (1887) p. 318. 



