Royal Microsco^pical Society. 47 



than the mouth of the apparatus. A gentle breeze was the most 

 productive. 



3rd. The amount of spores collected on the surface of the thin 

 glass varied from 250, the largest number counted, to one, and 

 ranged through 112, 87, 60, &c., to the minor number, some days 

 not furnishing one to be seen, on a careful examination with a -/o-th 

 objective. 



4th. The prevailing spores were small pale olive-coloured oval 

 spores, accompanied often with a small round rather darker olive- 

 coloured spore (Figs. 8, 26, 30), both apparently some form of smut. 

 Of the varieties of germs, &c., including chlorococcus, and what is 

 considered not a spore, but a cellular hair of some plant, though 

 figured, only 46 were noticed, and some of these are evidently two 

 or more phases of the same spore. The colour in the drawings has 

 been adhered to as strictly as possible, and the drawings made by 

 aid of the camera lucida at 300 diameters, as also the results figured 

 from a to z, obtained by cultivation. 



The number of days of exposure was 155 (19 in April, 24 in 

 May, 23 in June, 19 in July, 10 in August, 22 in September, 26 

 in October, 12 in November). The months of July and August 

 furnished by far the largest proportion of the daily collections. 

 The hours of exposure, except as intimated, may be taken during 

 the. long days as 10 to 11 hours, and the short days from 8 to 9 

 hours. 



In some cases the spores were seen to commence germinating 

 on the second day, others not before the twentieth day, and many 

 apparently of the same appearance under the microscope and on 

 the same thin glass did not germinate at all ; nor could it be said, 

 without trial, which was or which was not capable of growth or 

 living. Some of the spores which germinated quickly, early put on 

 a sickly aspect, whilst others, of apparently the same sort, grew 

 vigorously in the same cell. 



In very few cases the fungi formed their heads of spores or 

 conidia in the open air-chamber around the droplet of the culti- 

 vating solution, as some form of penicillium, whilst others did not 

 push their spore-bearing stems or fertile filaments beyond the edges 

 of the liquid, though the branchlets of the mycelium were often 

 extended to the edge of the cell. In some cases when the little 

 drop of fluid had receded from a thread and left it exposed to the 

 moist area only, it had the appearance of having its surface provided 

 with minute rootlets or hairs, as in Fig. u, and if left for any 

 time, it seldom recovered, by a change in position of the droplet or 

 by increased moisture admitted from the cultivating box, either its 

 original healthy condition or arrangement of the protoplasm. 



During the very hot days there was some difficulty in keeping 

 the quantity of the droplets of fluid constant by the supply of 



E 2 



