AMPHISPHAERIACEAE 201 



and, although there is no evidence that they weaken the wood, 

 they cause enormous losses by degrading the kimber. Conditions 

 favoring the development of these fungi and methods for pre- 

 venting losses are fully discussed in a report by Scheffer and 

 Lindgren (1940). 



Ophioceras albicedrae is of more than passing interest, for the 

 reason that it is commonly present on Jimipenis mexicana, pro- 

 ducing conspicuous white patches on the trunk and limbs. [Heald 

 and Wolf (1910)]. These patches are regarded as a specific 

 characteristic to be employed in identifying the tree. 



CucuRBiTARiACEAE. The Cucurbitariaccae are characterized by 

 the possession of stromata varying from a thin subiculum to a 

 rather thick pulvinate layer, upon which the perithecia are seated, 

 usually in caespitose aggregates. Most of them are saprophytic, 

 occurring on the stems of woody plants. 



The Cucurbitariaceae are quite like the Sphaeriaceae, and Fitz- 

 patrick (1923) has suggested that the two families be merged. 

 This suggestion arises from his critical study of the Subfamily 

 Nitschkieae, in which, within a single species, as among members 

 of the Genus Calyculosphaeria, there may be found an intergrad- 

 ing transition between a well-defined stroma and stromata con- 

 sisting of a loose, hyphoid subiculum. Furthermore the perithecia 

 of the Nitschkieae are all turbinate to cupulate in shape with a 

 tapering, sterile base. The closely related Genus Fracchiaea is 

 not cupulate but seems to be intermediate between the Cucurbi- 

 tariaceae, as delimited by Lindau, and the Nitschkieae. 



Amphisphaeriaceae. The perithecia of members of this fam- 

 ily are partly sunken in the substratum, with the upper portions 

 free. Among its representatives of ^^'orld-wide occurrence is 

 Caryospora piitamimim, commonly found on old pits of prunes 

 and peaches. This organism, recently studied by Jeffers (1940), 

 has large conical perithecia, and its asci usually contain three 

 large, fusoid, two-celled ascospores. He found that the five nu- 

 clei remaining within the young ascus after spore formation dis- 

 integrate. Spermogonia containing spermatia developed in cul- 

 tures on pea-extract agar, but Jeffers did not regard them as 

 essential for sexual reproduction. The problem of how this 

 organism thrives on sclerenchyma tissues is of more than passing 

 interest. 



