ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 103 



Development of the Perithecia of Venturia inaequalis.*— K. Killian 

 tias traced the formation and development of the sexual organs in this 

 Ascomycete, which develops on fallen leaves attacked by Fusicladium 

 dendriticum. A spiral hypha arises as a side branch and increases, the 

 inner cells of the spiral being more voluminous, the outer more elongate^ 

 the inner cells becoming ascogonial cells. The end cell grows to a 

 great length and functions as the trichogyne. The antheridia arise 

 from neighbouring vegetative hyphse in the form of finger- like growths 

 which surround the trichogyne. From the latter are formed processes 

 whicli press against the cells of the antheridium, the intervening 

 membrane becomes sieve-like and the nuclei of the antheridium enter 

 the ascogonial cells. 



Study of Hypocreaceae.t — -J. Weese has made a critical study of 

 genera and species as at present recognized. He dismisses the genus 

 Letendrsea, which is distinguished from Nectria by the brown colour of 

 the spores, and he does not recognize spore colour as a generic character. 

 In Nectria itself he objects to the consideration allowed to the presence 

 of a stroma or subiculum, nor does he think that hairs on the perithecium 

 are a character of any systematic significance. The only constant 

 feature is, he considers, the form of the perithecial wall. Weese 

 describes some new species of Nedria, but he sinks N. Rihis and 

 N. guaranitka. 



Drepanoconis and Clinoconidium.J — A. Maublanc has studied these 

 genera and finds that they are closely related in structure and life- 

 history. They induce gall formations on their host-plants, and have 

 been classified by the author under Melanconise. With these two 

 genera he associates Coniodictyum, parasitic on Rhamnacese in S. Africa. 

 The other members of the group are S. American and grow on a species 

 of Lauraceas. 



Endoconidia of Thielavia basicola Zopf.§ — W. B. Brierley dis- 

 cusses the formation of endoconidia, especially in the above fungus, of 

 which he has made a thorough study. The conidia in this case are 

 not endospores formed by free cell-division within a cell ; they are 

 acrogenously abjointed from the conidiophore. The latter is slightly 

 bulbous in its basal portion and possesses an elongated tapering, or 

 almost linear, apical region. Large vacuoles are usually present and 

 not infrequently contain oil-drops. The nucleus lies in the basal 

 portion of the cell. 



The first conidium is liberated by the differentiation of its walls into 

 an inner wall and an outer persistent sheath which bursts at the apex. 



* Ber. Deutsch. Bot. Gesell., xxxiii. (1915) pp. 164-8. See also Bot. Centralbl., 

 cxxix. (1915) pp. 440-1. 



t Centralbl. Bakt., xlii. (1914) pp. 587-613. See also Bot. Centralbl., cxxix. 

 (1915) p. 442. 



X Bull. Soc. Mycol. France, xxx. (1915) pp. 441-9 (2 pis.). 



§ Ann. Bot., xxix. (1915) pp. 483-93 (1 pi. and 1 fig.). 



