MICHIGAN ACADEMY OF SCIENCE. 121 



comparison of descri])tioiis of all Phonia, Cj/tospora, mikI Cotiio- 

 ihyr'iHin s])eeies oiveii in the Syllose on the basis of spore size, 

 chaiactcr <if the conidiojthore, cdlor nl' the sjiorcs and character 

 (d" the jncnidinni. I Hnd this species agrees most nearly with the 

 fnnuns in (picslion. The following' is Saccardo's description: 



Apospliacria fvisco-macnlans, Sacc. ^lich. II j). 275 (IMionia). 



Peritlu'ciis late jirciiariis, li<>no snperfice infnscato, senii-v. fere 

 (otis inimersis, \- mill, diam., globnlis v. snbcompressis, nifjris; 

 ostiolo obsolete; sporulis oblongis, nterinqne rotnndatis, 5=1 — IVt 

 dihitissime olivaceis, basidiis fascicnlatis deorsnm incrassatis 8=2, 

 hyalinis sntTnltis. 



Hab. in liiino decorticato Piri mali, in Ttalio bor. — afflnis Aposp. 

 fnscicidae Sacc. a qua basidiis, matrice infuscata, etc., satis recedere 

 videtnr. (Sacc. 3: 174.) 



In only one particular, the superficial discoloration of the host 

 tissue, does important variation in the description of the two or- 

 ganisms occur. It would seem considering the discoloration which 

 might occur on weathered decorticated apple limbs, that this por- 

 tion of the description need not be adhered to strictly. Accordingly 

 in view of the other points of accordance, which are so close on 

 various points — host, spore size and color, basidium size and color, 

 morj>hology of parts, — as to make coincidence almost out of the 

 question, it seems safe to assume that the fungus found in ^lichigan 

 is the sjtccies Saccardo described for Italy. 



Diedicke* has recently been working over many of the species 

 of the Sphaero])sidales and his work has attracted great attention. 

 Diedicke's recommendations have found much favor with American 

 Avorkers and it can not be gainsaid that some of the segregations 

 which he has emphasized are groups of marked coherence and 

 form excellent working units. Diedicke has emphasized the charac- 

 ter of the jjycnidial wall as a basic character in this division of the 

 Fungi Tniperfecti. If the wall in the Phoma-like forms be thin 

 and evidences of stroma are lacking, we have, according to Diedicke 

 the true Phoinafi. If the wall be otherwise. Diedicke makes use of 

 the two genera Phomopsis and Plowdomiis. These genera are 

 closely related and have been generally confused. In both we have 

 a thick wall and a hymenium more or less irregularly folded. In 

 Phomopsis the chand)er is not equipped with a wall entirely com- 

 fdete, for the base in this genus is made up of the loose mat of 

 fungus and host, and is not darkened. In Plenodomus the wall is 

 distinct throughout. Phomopsis has a wall of four layers, in Pleno- 

 domus two layers. 



►Difdicko 11.. Di.- Onttniig Phomopsis. .\nii. Myc. 9 :1.37-141, 1 pi. 1911. 



