490 SUMMARY OF CURRENT RESEARCHES RELATING TO 



two or three daughter-cells, one of which remaius sterile, wliile tlie 

 others put out slender branches. According to the vigour of the 

 individual one or more branches of the spirally coiled filaments are 

 able to develope asci. 



The author then describes in detail the structure and development 

 of Ctenomyces serrntus, representing a new genus of the family, which 

 sprang from a moist bird's feather. On the quill was found a 

 sclerotium-like resting mycelium distinguished by numerous comb- 

 and hook-like projections, consisting of from eight to ten cells, each 

 of which put out, and always on the same side, a more or less curved 

 appendage, which gave the peculiar comb- or rake-like appearance to 

 tlie whole structure. From this mycelium there grew upwards a 

 delicate hyphal web, which produced first conidia and subsequently 

 asci. The conidia vary in form. In the simplest form long branches 

 of the mycelium produce the conidia on short erect pedicels, some- 

 times directly, sometimes on short lateral branches. They are club- 

 shaped, 1 or 2-celled, 5" 5 to 6*5 /x, long, and 2-S fx broad. In other 

 cases a smaller or larger number of conidiophores are congregated 

 into a tuft, and each of them is usually branched abundantly and in 

 an extremely regular and beautiful manner. The branches spring 

 one generation from another almost exactly at a right angle. Thirdly 

 there are agglomerations of conidia which closely resemble the 

 bundle of asci. These occur only in feeble specimens. The ascus- 

 aggregations of Ctenomyces are spherical or ovoid, 5-1 "5 mm. in 

 diameter, and consist of a dense, broad, colourless enveloj)e closed on 

 all sides, and composed of numerous loosely mterwoven hyphfe. 

 The hyjjlife are sometimes torulose and composed of roundish or top- 

 shaped cells, sometimes furnished only on one side with lumps and 

 teeth, but displaying in both cases a beautiful structure. The ends 

 of the hyi^hal branches are often elongated into long, slender threads 

 which are coiled in a very regular manner. The envelope or pericarp 

 attains a thickness of .50-80 y., and encloses the outermost bundle, 

 which is comi^osed of densely packed asci rendered polygonal by 

 pressure. 



The development of the aggregation takes place as follows : — 

 Its first rudiment appears in the form of a short branch which some- 

 what swells out above, and is embraced by a hy( ha, originating either 

 from the same or from a neighbouring mycelial hyjiha. This hypha 

 coils more and more firmly, in from 1 to 8 spirals, round the club- 

 shaped branch which grows only slightly in length. The sjjiral 

 hypha has now a number of septa, and each of the cells thus formed 

 increases in length, and the coils thus become broader, and often 

 stand in great curved lines away from the club-shaped bi'anch. 

 Branches then shfjot from them, the lowermost serving ns organs of 

 attachment, the rest jn'oducing tufts of asci. The club-shaped branch 

 in the middle of the ball has in the meantime divided into three cells, 

 of which the uppermost is nearly empty and may be comj^ared to the 

 sterile cell of Gymnoascus. The envelope or pericarp originates from 

 the mycelium, a great number of the hyphse branching copiously 

 around the ball while it is still voung. Most of these branches then 



