RESEARCHES ON THE MUCORINI. 61 



second day in the saline solution or the decoction, both of 

 which are feebly nutritive liquids and in Avhich its vegetative 

 activity is soon exhausted ; in orange juice this did not take 

 place till the third day. In both cases the temperature was 

 about 59° Fahr. Abruptly-svvollen branches, club-shaped in 

 form, make their appearance upon the hyphae both in the 

 nutritive medium and in the air. Sometimes these branches 

 prolong themselves directly into an equal number of sporangi- 

 ferous hyphfe ; but most frequently they first divide at their 

 swollen apices into numerous branches of which ordinarily one 

 (fig. 15), sometimes two or three (fig. 16), develope into spo- 

 rangiferous hyphse, while the rest, which are short and pointed, 

 form a tuft of rootlets. Sometimes these rootlets reduce 

 themselves to one or more rounded protuberances situated 

 towards the base of the sporangiferous hypha and giving to 

 its lower region an undulating outline. The sporangiferous 

 hyphse of Phycomyces are normally therefore produced in 

 groups, and this is indicated generally by the presence of 

 sterile hyphse, in the form of rootlets. This is a second 

 character which separates our plant from Mucor, and indi- 

 cates a nearer affinity with Rhizojms. 



There are often also a certain number of the branche.s 

 which are swollen into a club- or pear-shaped form and 

 do not erect themselves above the surface ; instead of pro- 

 ducing a sporangiferous hypha, which would seem to have 

 been their first destination, they become abruptly attenuated, 

 and are merely prolonged into a mycelial filament (fig. 17). 

 But the protoplasm never aggregates in the interior of these 

 basal swellings of the mycelial ramifications, even to the 

 extent of simulating a chlamydospore, and we have never, 

 indeed, under any circumstances, met with a single one in 

 Phycomyces. Occasionally when the process of germination 

 has been prematurely arrested, as by the development of bac- 

 teria in the decoction, certain portions of the hyphse, in which 

 the protoplasm preserves its vitality after the rest of the tube 

 is destroyed, are partitioned off. Tliis is certainly a tendency 

 towards the formation of chlamydospores ; but there is no 

 condensation of the protoplasm, and it never invests itself 

 with a special membrane. Later on, as in the case of the 

 spores, this isolated protoplasm undergoes a gradual altera- 

 tion separating into tolerably regular ovoid or fusiform 

 nodules, which to a certain extent have the appearance of 

 spores contained in an ascus but appear to be incapable of ger- 

 mination. The figure 3 h represents one of these cavities, 

 which happens to have been formed at the very base of the 

 germinating hypha, and corresponds to the original cavity 



