204 DIVISION II. — COURSE OF DEVELOPMENT OF FUNGI. 



the shape of a hollow spiral with four or five turns which lie close to one another. 

 The spiral is divided by transverse walls into about as many cells as there are turns. 

 Then two or three slender branchlets grow from the lowest turn in the direction of 

 the apex, and are closely applied to the surface of the spiral; one of these gets in 

 advance of the rest and is the first to reach the apex ; there it lays its upper 

 extremity on that of the spiral filament, and, if we may trust our observations, 

 the two filaments conjugate, that is, their protoplasmic bodies unite by the dis- 

 appearance of the intervening membranes. Sometimes the branch which anticipates 

 the rest is seen to grow up inside the spiral, and then the conjugation cannot be so 

 certainly ascertained; from its behaviour it must be regarded as the antheridial 

 branch. When it has reached the apex of the spiral it is followed by the rest, and 

 now all of them put out new branches which become so interlaced and divided by 

 transverse walls that the spiral is soon covered by a compact layer of isodiametric 

 cells. The lowest turn of the spiral itself participates in the formation of this layer, 

 which surrounds the rest of the spiral, the ascogonium-hypha, as the perfectly closed 

 outer wall of the globular sporocarp. The cells of the outer wall do not divide 

 again ; but while the sporocarp increases considerably in volume they grow in the 

 direction of the surface into a tabular form, and secrete on their outer membrane, 

 which continues thin and colourless, a golden-yellow substance readily soluble in 

 alcohol in the form of a thick brittle pellicle. Branches shoot out, as in Erysiphe, 

 from the inner surface of the cells of the outer wall, as soon as these have united, 

 and ramify and become interlaced and soon form an inner wall of many layers, 

 while fresh branches from them push in between the loosening turns of the spiral, 

 and fill the space between it and the outer wall with a tissue composed of thin-walled 

 cells rich in protoplasm and without interstices. The growth of this tissue causes 

 the sporocarp at first to increase in volume in every direction and constantly forces 

 the coils of the spiral ascogonium further apart. When it has reached a certain 

 point, the spiral begins to put out numerous branches, the ascogenous hyphae, which 

 thrust themselves in between the inner wall-cells in every direction, and replace 

 them, and the many extremities of their numerous ramifications become ovoid 

 eight-spored asci. The continuity of the ascogenous hyphae is more and more lost 

 as the asci are formed, so that as the spores begin to ripen the outer wall encloses 

 only asci and the remains of the hyphae and the cells of the inner wall, and at 

 length the walls of the asci themselves disappear and the sporocarp contains scarcely 

 anything but ripe spores. 



3. According to Brefeld's researches, the development of the sporocarps of 

 Penicillium glaucum also begins with the appearance of a spirally twisted hyphal 

 branch. But here we find in the first stages that are open to observation two similar 

 branchlets surrounded by felted mycelium, which always arise close to one another 

 and are spirally twisted round one another in one or two turns; whether they are 

 morphologically and physiologically of equal or unequal value cannot be directly 

 determined, and the further development gives no certain information on this point, 

 so that we can only speak of a distinction between archicarp and antheridial 

 branch of like form with it from the analogy of the otherwise nearly related Eurotium. 

 Then from the spirally twisted body — whether from one only of its component 

 parts or from both is not ascertained — short ascogenous hyphae grow out as branches 



