94 4 DIVISION I.—GENERAL MORPHOLOGY. 
begins an extremely thin lamella of the wall, not previously distinguishable, suddenly 
splits off at the apex of the ascus, and the inner lamella issuing through it lengthens 
in a few seconds into a tube nearly three times’as long and as broad as or broader 
than the original ascus; the lower part of the tube continues to be attached to the 
torn outer lamella (Fig. 46 A). The wall of the elongated tube is of about the same 
thickness as that of the original ascus-wall. The eight spores follow pari passu 
the apex of the elongating tube, keeping as nearly as possible their original grouping, 
the uppermost one being close to the apex. ‘Soon the uppermost spore is seen 
to have moved into an aperture which has formed in the terminal point of the tube 
and then to be ejected through it with great force. As soon as this has happened, 
the tube shortens by about half the length of a spore, so that the second spore 
now touches the point of the tube and is pressed into the aperture, which it stops 
up. Then the tube elongates again to its original length and the second spore 
is then ejected with the same force as the first. The entry of all the remaining 
spores into the opening and their successive ejection is accomplished in the 
same manner. Finally the empty tube, which is open at the apex, contracts rapidly 
to about 3 of its length while the membrane continues to swell considerably, and 
eventually becomes disorganised without undergoing further changes. The whole 
proceeding occupies only a space of a few minutes. It is evident that we have 
in this case a modification of the discharging mechanism, the chief point in which must 
be that the width of the apical aperture is too small for a simultaneous discharge of the 
spores ; but the question requires further investigation. 
Successive ejection is at present certainly known only in a few Pyrenomycetes. 
That it should occur also in the open hymenia of Discomycetes is not probable; a 
brief statement of Crouan! about Vibrissea can scarcely be used here, and moreover 
needs confirmation. In the Pyrenomycetes with which we are concerned here the 
asci, like those represented in Fig. 44, are packed close together at the bottom 
of perithecia with a narrow canal-like orifice, and when they elongate they thrust them- 
selves one after another through the canal without becoming detached from their 
insertion till their upper extremities are free from the perithecium, and then ejection 
takes place. Woronin was the first who described these proceedings correctly in 
Sphaeria Lemaneae?. His account holds good also of Sphaeria Scirpi, Phyllachora 
Ulmi, and Cordyceps militaris. The tops of the asci may be seen emerging one after 
another from the ripe perithecia of the latter species in a damp atmosphere, and 
ejecting their spores. Each rises about six times its own diameter above the mouth 
of the perithecium; in a few minutes the slender filiform spores fly one after another 
with the speed of an arrow from the tip of the ascus; each of these successive 
ejections is followed by a slight but permanent shortening of the ascus, which 
reaches the level of the orifice of the perithecium as the last spore is ejected. 
The ejection of spores from the perithecia of Claviceps, which was observed 
by Tulasne® and may be seen with the naked eye as a puffing out of fine minute 
glistening needles, is undoubtedly produced in the same way as in Cordyceps, and my 
explanation of it at page 145 of my first edition was in the main incorrect. It would 
appear from the accounts which we possess that the same or similar processes are 

1 Ann, d, sc. nat. ser. 4, VII, p. 176. 2 Beitr. III, p. 5. ® Carpol. I, p. 42. 
