480 TUB SOOTY MOULD OF CITRUS TREES, 



The pavaphyses are hyaline, elongated-clavate, usually with 

 finely granular contents, same length as ascus and 9J /x. at 

 broadest part. 



The asci and paraphyses arise alongside of each other from 

 short chains of colourless cells. 



Asci were met with in various stages of development, and the 

 sporidia pass through different coloured stages. At first the 

 contents of the ascus are finely granular, almost completely 

 filling the interior and having a small oval nucleus towards the 

 centre. Then the differentiation of this homogeneous mass into 

 colourless sporidia takes place. As they grow they assi;me a 

 very pale green tint, and finally become brown, while they no 

 longer fill the ascus, as the space between the topmost sporidium 

 and the outer wall of the ascus may be 9|^ /x. 



It is worthy of note that these changes of colour fi-om hyaline 

 to yreen and from green to brown in the course of development 

 of the sporidia may turn out to be characteristic features of the 

 genus Capnodium. At any rate in the closely allied genus 

 Meliola I found the sporidia to pass from hyaline to yeUow, and 

 from yellow to brown;* and in Plenspora lierharuin, Pers., they 

 are first hyaline, then yellowish, and finally yellowish-brown, f 



Only a few mature sporidia were found, and as none of the 

 perithecia met with had opened they are probably ripe as a whole 

 later in the season. 



The perithecia are the most characteristic of the reproductive 

 bodies from their containing asci. They most resemble the 

 spermogonia externally, but they are larger and less symmetri- 

 cally shaped. They are quite distinct from the pycnidia, and 

 yet Dr. Cooke in his recent excellent " Introduction to the Study 

 of Fungi" (1895) has confounded them. He writes: — "The 

 genus CajmoJiiini is distinguished by elongated large perithecia, 



* Proc. Linn. Soc. N.S.W. 1896, Pt. 1, p. 104. 



+ On the Life-history of Macrosporium parasiticum, Thuem., by Kingo 

 Miyabe. Ann. Bot. iii. No. ix. 1889. 



