132 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



long since observed by Carus,* that the portions of a salaman- 

 der which were above the surface of the water produced a 

 Mucor, while those immersed gave rise to an Achlya. In the 

 simple species, the endochrome in the clavate tips gradually 

 becomes organised, producing subelliptic bodies with two 

 lateral appendages, by means of which they are enabled to 

 move with great celerity. These escape either by a lateral, or 

 more frequently by a terminal aperture ; and as soon as the 

 contents are discharged, the dissepiment becomes convex, the 

 penultimate joint swells, and gives rise to a new fertile articula- 

 tion. This process is repeated till the vital powers of the 

 threads are exhausted. In Achlya prolifera, however, the 

 new sporangia are formed after the manner of the branchlets 

 of a Gladophora, on either side, at the base of the effete joint ; 

 and this process being repeated, we have a bifid thread. In 

 this case also, the spores have two flagelliform appendages, and 

 in both they give rise to new plants, sometimes germinating 

 in situ, sometimes after the discharge of the spores, when de- 

 tained by means of a delicate membrane, in the shape of a glo- 

 bose head. The flagelliform appendages in Saprolegnia ferax, 

 as observed by Thuret, are terminal. The globular sporangia, 

 observed by the same admirable writer, with their spores, re- 

 semble so closely those of some of the mucorine Fungi, that I 

 should not hesitate, were there any other instance of the produc- 

 tion of zoospores with flagelliform appendages amongst -Fungi, 

 about their removal from Algae. There is stUl room for further 

 investigation, and, perhaps, some Hght may be thrown upon 

 the question by examining the growth of the mould, which 

 attacks living flies in autumn under different circumstances. 

 It will, I think, eventually appear that the Empusa of the fly 

 is but a form of Botrytis Bassiana, and if so, the fungal 

 nature of these productions will be placed beyond doubt. The 

 cellulose of which their vesicles are composed, presents a beau- 

 tiful blue tint under iodine, and is apparently far purer than 

 in most Fungi or Algse. 



1 Ot). A large quantity of the Con/ervacece consist of simple 

 unbranched articulated threads, increasing in length by con- 

 * Act. Nov. Leop. 182 



