MUCOR 499 



the rupture, gradually distend, and may be recognized 

 as consisting of 



4. Numerous oval spores, with smooth walls. 



5. An intermediate mucilaginous substance which 

 is capable of swelling, and thus effects not only the 

 bursting of the sporangium, but also the dispersal of 

 the spores. 



6. After the swelling and dispersal of the spores are 

 complete, there will be seen remaining a spheroidal body 

 (the columella), which is the distended septum of 

 separation of the sporangium from the gonidiophore : 

 round its base may often be traced the remains of the 

 wall of the sporangium as a ragged fringe. 



The minute projecting bodies on the surface of the sporangium 

 are not of constant occurrence, though often present : they consist 

 of oxalate of lime. 



According to the conditions of nutrition of the Fungus, there 

 may be very considerable variety in the size of the sporangia, and 

 in the number of the spores produced : under peculiar circum- 

 stances the sporangia may be of so reduced a form that the 

 columella is absent, and the number of spores may be less 

 than ten. 



As a second type Pilobolus crystallinus may be taken : this 

 Fungus appears with great constancy on dung of the horse or cow, 

 if kept under a bell-glass for about ten days : it is specially in- 

 teresting because of the mechanism for shooting off the spor- 

 angium bodily from the gonidiophore. The sporangia may thus be 

 commonly found adhering to the inner surface of the bell-glass 

 which covered the culture. 



IV. With similar precautions to those taken in the 

 case of the spores of Eurotium Aspergillus (p. 486), 

 sow spores of Mucor in a drop of a sterilized decoction of 

 horse-dung, or of French plums, or other suitable 



K K 2 



