PSALLIOTA CAMPESTRIS 433 



right-hand drop is about eight seconds old and of nearly maximum 

 size, which indicates that the spore to which it is attached should 

 be shot away after the lapse of about two more seconds. The 

 other drop is only about two seconds old and therefore will continue 

 to grow for about eight more seconds. The spores on both no. 32 

 and no. 24 are about eight hours old. No. 16 bears fully pig- 

 mented spores, which we may suppose to be six and one-half hours 

 old and therefore an hour and a half from the moment of spore- 

 discharge. No. 11 also has fully pigmented spores. These we may 

 suppose to be five and a half hours old and therefore two and a 

 half hours from the moment of spore-discharge. Nos. 5 and 3 may 

 be supposed to have begun their development at the same moment. 

 Their spores are becoming strongly pigmented, and we may there- 

 fore suppose that they are about four hours old and four hours 

 from the moment of spore-discharge. 



The basidia of the middle part of the second wave will now be 

 described. No. 61 bears spores which are becoming pigmented. 

 We may suppose them to be three and a half hours old. No. 57 

 bears a single sterigma and a spore of full size but unpigmented. 

 We may suppose the spore to be two hours old. No. 53 bears 

 two spores of full size but unpigmented. We may suppose them 

 to be one hour old, so that they attained full size only twenty 

 minutes ago. Nos. 48 and 44 bear spores which are far below 

 full size and about ten minutes old. The spores on no. 41 are 

 only five minutes old. No. 36 bears full-grown sterigmata but no 

 spores as yet. It resembles hi outward form a basidium which 

 has just shot away its second spore, i.e. such a basidium as no. 32 

 will be within two seconds when the left-hand spore has been 

 discharged. But one can easily distinguish between a basidium 

 which is just about to develop its spores and one which has just 

 discharged them, for there is a marked difference in their cell- 

 contents. The former has a basidium-body filled or almost filled 

 with protoplasm, while the latter has a basidium-body occupied 

 by one large vacuole. No. 28 bears sterigmata about two-thirds 

 developed, and no. 18 sterigmata about one-third developed. 

 Finally, no. 8 shows as yet not even a trace of sterigmata. 



We shall complete the account of the basidia entering into the 

 VOL. n. 2 F 



