496 SUMMARY OF CURRENT RESEARCHES RELATING TO 



finally divides to form spores. The author was unable to follow the 

 stages of division, but certain appearances indicated karyokinesis. He 

 sees in the process a true heterogamic conjugation of two different 

 gametes. 



Parasitism of Laboulbeniaceae.* — F. Picard has made a study of 

 these fungi, and advises the collector where and how to gather them. 

 They are heteroecious plants, and as their propagation depends on the 

 (•(intact of adult plants growing often on different hosts, they frequent 

 almost exclusively insects that congregate together. Solitary insects are 

 thus free from the parasites. Moist atmosphere also is essential to their 

 development. 



In another paper f Picard describes a marine form parasitic on 

 Aepus Robini, which lives in clefts of the rocks under shelter of 

 LaminarisB. This marine Laboulbenia does not alter the chitinous sub- 

 stance : it probably lives on the waxy matter that covers the bodies of 

 insects. 



Rare Pyrenomycete.lj: — C. Engelke gives a careful description with 

 figures of Nummularia lutea, which is found on old alder stems. The 

 stroma is yellowish-brown, but becomes black through the expul- 

 sion of the dark-coloured spores. Under water, the asci, paraphyses 

 and hyphae dissolve into a gelatinous mass, and are ejected from the 

 perithecia along with the spores, so that in damp weather, not only the 

 stroma, but the surrounding wood is covered with a dark gelatinous 

 mass. 



Erysiphacese.§ — J. P. Anderson gives an account of the genera and 

 species of this family that occur in Iowa. Each species is carefully 

 described, and localities and host-plants are added. Note is taken of the 

 parasite Ampylomyces quisqualis, that lives on all kinds of Erysiphaceaj 

 and evidently serves to hold them in check. A host-index is published. 



Gr. Cuboni and L. Petri || report the perithecial stage of a Sphsero- 

 theca on peach trees. It differed specifically from S. pannosa, and they 

 suggest that it may be the fruiting form of the oak mildew of which 

 the conidial stage only is knowm, and which had been very prevalent in 

 the same neighbourhood. 



North American Hypocreales.lf — F. J. Seaver publishes a second 

 study of this subject. In the present paper he discusses Nectria Pcziza, 

 a well-determined Nectria, although the type specimen is not now in 

 existence. The plants are often crowded, but there is no true stroma, 

 and they collapse at maturity so as to resemble a cup-fungus, hence the 

 specific name Peziza. Seaver includes a number of species as synonyms 

 under this plant, and gives diagnosis and drawings. 



In another paper Seaver** gives- an account of several new or note- 



* Peuille jeunes Naturalistes, xxxix. (1909) pp. 29-34 (1 pi.). 

 t C.R Soc. Biol. Paris, lxv. (1908) pp. 483-6 (2 figs.). See also Bot. Centralbl., 

 ex. (1909) pp. 336-7. % Arm. Mycol., vii. (1909) pp. 176-81 (8 figs.). 



§ Proe. Iowa Acad. Sci., xiv. No. 35, 33 pp. (3 pis.). 

 || Atti R. Accad. Liucei, xviii. (1909) pp. 325-6. 

 If Bot. Torrey Bot. Club, xxxvi. (1909) pp. 201-4 (1 pi.). 

 ** Mycologia, i. (1909) pp. 19-22 (1 pi.). 



