156 DIVISION II. COURSE OF DEVELOPMENT OF FUNGI. 



' sphere-yeast ' or ' mucor-yeast,' partly from its resemblance in shape to the Saccharo- 

 mycete of yeast and partly from its power of exciting alcoholic fermentation. Under 

 certain conditions the sprouts behave like spores of Mucor. 



All the gemmae which have now been described are capable of developing by 

 germination into normal mucor-mycelium, either at once or after a prolonged period 

 of rest, if properly fed and supplied with air. Each gemma of Mucor racemosus, 

 cultivated in moist air without supply of food, is capable of developing at the expense 

 of its protoplasm into a typical but very minute sporangiophore with a sporangium 

 containing in extreme cases not more than eight spores (Brefeld). 



Doubtful Mucorini. i. Sorokin 1 has described under the name of Zygoehy- 

 trium aurantiacum a Fungus which grows on dead insects beneath the water, and 

 which if that writer's observations are confirmed is a small species of this group adapted to 

 growing in water. The entire plant consists of an erect tube with two bifurcations, alto- 

 gether scarcely o.i mm. in height, attached to the substratum by short lobes at its base 

 without any proper mycelium. Globular sporangia producing numerous swarm-spores 

 with one cilium as in the Chytridieae (see section XLVI) are formed at the extremities of 

 the branches; and a zygospore is also produced at the first bifurcation in perfect specimens 

 in the manner which has been described in the case of Mucor. The course of 

 development is in other points like that of Mucor. These observations have yet 

 to be confirmed. 



2. Van Tieghem 2 describes under the names of Dimargaris cristalligena and 

 Dispira cornuta two Fungi growing on dung, which have very peculiar gonidiophores, 

 but otherwise agree with Piptocephalis in being parasitic on the Mucorini, in the 

 mode in which they enter the cells of their host, in the presence of transverse walls in 

 the gonidiophores and in the chains of gonidia. The genesis of the gonidial chains is 

 not indeed fully described, but the drawings would seem to show that it is similar to 

 that of Piptocephalis. It is as yet by no means certain that these Fungi belong to the 

 Piptocephalic group, but this affinity is highly probable, since we know of no species 

 outside the Mucorini which they approach in form. The point can only be decided by 

 the discovery of zygospores or some structure homologous with them. 



3. The same may be said of a small group, which may be called the Coemansieae, 

 consisting of Coemans' Kickxella and Martensella and Coemansia of Van Tieghem 

 and Le Monnier. The mode of life of these Fungi, of Kickxella at least and Coemansia, 

 is the same according to Van Tieghem as in Piptocephalis. In the structure of their 

 gonidiophores, the only part at present known beside the mycelium, they differ materially 

 from the acknowledged members of the group of the Mucorini. Their common and 

 chief peculiarity consists in the possession of basidial branches of somewhat fusiform 

 appearance, falcately curved, and divided by transverse walls into several cells from which 

 on the concave side of the branch numerous spores, placed close together in two or more 

 comb-like longitudinal rows, are abjointed both simultaneously and one by one. The 

 spores themselves are narrowly fusiform, pointed at both ends, and emit their germ-tubes 

 at right angles to their own longitudinal axis. Basidial branches of this kind form in 

 Kickxella a whorl of 6-14 members with their concave sides upwards on the apex of the 

 erect septate filament that bears them, which is elsewhere usually unbranched and is 

 scarcely 0.3 mm. in height In the other genera they stand singly in racemose 

 arrangement on the dichotomously ramifying branches of the gonidiophore. No 

 zygospores are known ; but Coemans and afterwards Van Tieghem and Le Monnier 

 found small ascomycetous sporocarps in the neighbourhood of the gonidiophores ; 

 whether they belonged to each other is a very doubtful question. 



1 Bot. Ztg. 1874, p. 305. 2 Van Tieghem, II. 



