154 SEVENTEENTH REPORT. 



them to the air as short a time as possible. The Petri dishes were 

 then sealed with a gummed label, on which was written the data. 

 After return to the laboratory, the soil sami>les were generously 

 moistened with sterile water, drops of which were transferred to 

 agar plates with a platinum needle. From these one additional 

 transfer usually gave a culture free from contaminations, and from 

 which a single spore culture could be made. 



On bread Cunninghamella elegans forms a white, slightly ashey, 

 cottony mass up to 3.5 cm. tall. In older cultures the mycelial mass 

 becomes darker, reaching a pale, grayish-tan. No sporangia are 

 formed, but asexual reproduction takes place by means of conidia. 

 The conidiophores are erect, more or less branched, with, or without 

 septa, and terminate in spherical heads o9-51 microns in diameter^ 

 furnished with papillae, which are the points of insertion of the 

 conidia, sometimes the persistent pedicels of the conidia. Below this 

 terminal sporiferous head, there is usually a whorl of smaller coni- 

 dia-bearing heads, up to 23 microns in diameter. The number of 

 branches in the whorl is generally three to five, but varies somewhat. 

 Not seldom the conidiophore forms a swelling, similar to an early 

 stage in the formation of a sporiferous head, but. from which arise 

 branches, which may bear conidia at their swollen distal ends, or 

 may end in a sterile tip. 



The conidia arise as a simple projection from the sporiferous head, 

 which enlarges at the tip and is finally cut off by a wall. The 

 conidia borne on the terminal sporiferous head are oval to pyriform 

 and measure 16-21 x 12-lG microns, those on the lateral swollen heads 

 are spherical or slightly oval and are from 10-16 microns in diameter. 

 The membrane of the spores, in many cases, is furnished with very 

 delicate spines, which may equal one-half the diameter of the spore 

 in length. Sometimes, however, the spines are very short and incon- 

 spicuous, or in some cases the membrane of the spores appears prac- 

 tically smooth. 



This mucor is also readily cultivated on bread, agar, etc. 



BIBLIOGRAPHY. 



1. Bainier, G. Bull. Soc. Bot. Fr. T. 27, p. 226-228. PI. V. fig. 

 5-10. 1880. 



2. Blakeslee, A. F. Two conidia-bearing Fungi. Cunninghamella 

 and Thamnocephalis. Bot. Gaz. 40:3. p. 161-170. PI. VI. fig. 1-11. 

 1905. 



3. KaufTman, C. H. A Contribution to the Physiology of the 

 Saprolegniaceae, with special reference to the variations of the 



