522 Lew ton- Brain. — Cor dy ceps cphioglossoides (Ehrh). 
The material with which this research has been carried on 
was given me by Prof. H. Marshall Ward, who collected it in 
the autumn of 1900 in Scotland. The tubers upon which it was 
parasitic were those of Elaphomyces variegatus. The greater 
part was fixed in ordinary methylated spirit, some part in 
Kieser’s solution. The chief stains used were Delafield’s and 
Heidenhain’s haematoxylins. I also tried Flemming’s and 
Hermann’s safranin - gentian - violet double stains, but the 
material was not fixed well enough to permit the use of these 
with advantage. 
Structure and Development of Asci and Spores. 
Unfortunately all of the material at my disposal was mature; 
none of it showed any young stages in the development of the 
stroma or perithecium. 
The cavity of the mature perithecium is roughly egg-shaped 
(Fig. 2) ; it passes above into a very narrow neck, and this 
opens at the top of small, flattish papilla. 
The general mass of tissue of the fertile part of the stroma 
is very loose: it would appear to have been pulled apart by 
the growth, during the development of the perithecia. The 
outermost layers, however, are composed of closely woven 
hyphae, which run for the most part parallel to the short axis 
of the stroma and transversely to the long axis. 
The wall of the perithecium itself is also composed of closely 
woven parallel-running hyphae. This gives the perithecium 
the appearance of being an invagination of the surface layers 
of the fertile stroma. 
The hymen ium occupies the basal part of the perithecium- 
cavity : the hyphae of which it is composed are closely packed 
and run parallel to the long axis of the perithecium. 
In a mature perithecium the cavity is occupied by a large 
number of very long cylindrical asci in all stages of develop- 
ment. This continuous development of asci alone rendered 
it possible for me to obtain different stages in the formation of 
the spores. When mature, the asci extend up to the neck of 
