THE FLOE A OF NEBRASKA. 51 



4. UYDROOSM Wiggers PL Holsat. 110. 1780. 



Sporangiophores simple, arising singly from swellings in the mycelium, color- 

 less or orange, above expanding into a large ellipsoid swelling; sporangia 

 hemispherical or lens-shaped, many-spored; [the membrane above black 

 and cuticularized, the lower half quickly disappearing and leaving the 

 upper part resting on the conical columella; both at maturity thrown off 

 by tension of the terminal swelling of the sporangiophore; zygospores,, 

 naked, borne on tong-shaped branches. 



Etymology: Greek vSup, water, and Latin gero, to carry. 



Hydrogera obliqua (Scop.-) OK. Rev. Gen. 855. 1891. 

 Mucor obliquus Scopoli Flor. Carniol. II., 494. 1772. 

 Hydrogera erystallina Wiggers 1. c. 



Pilobolus crystallinus Tode Schrift. Naturf. Freund. Berl. V. 46. 1784. (Ex 

 Fischer). 

 Sporangiophores arising singly from a bladder-like swelling of the mycelium,. 

 5-10 mm. long, the terminal swelling ellipsoid or ovoid, .85-l.30x.60-.85 

 mm. ; sporangia plano-convex, resting on the side of the terminal swelling 

 300-400x100-150 fi\ columella conical; spores elliptical 5-10x3-6 //, color- 

 less, but in mass greenish yellow. 

 On dung, on ground in greenhouse, not uncommon. PL XI V, Fig. 5, a. 



[Mortierella has a distinct fertile mycalium from which the sporangiophores arise 

 singly or in groups, the bases being enveloped in a mass of short branches. 

 The sporangia are many-spored and have no columella. The zygospores 

 are covered with a dense mass of hyphae, which branch off from the 

 suspensor-cells and the branches from which the latter arise. M. poly- 

 cepliala Coemans, distinguished among other things by its branched 

 sporangiophores, grows on dung and on decaying pore fungi. It has been 

 reported from the United States, and should be found here.] 



Sub-fam. — Chaetocladieae. — Asexual reproduction by conidia which are borne 

 singly (i. e., not in chains) in groups on the swollen middle portion of 

 branches of the conidiophbres, the ends of which are sterile. 

 Through the Thamnidieae, one of the tribes of the Mucoreae, not represented 

 in our flora, this group is connected with the Eumucoreae. The grada- 

 tions shown by other forms and produced by cultivation make it reason- 

 ably certain that the conidia are to be regarded as reduced one-celled 

 sporangia. 



5. CHAETOCXAMUM Fresenius Beitraege 97. 1853. 



Parasitic upon other Mucoraceae, mycelium thin, colorless, forming clusters 

 of short, thick haustoria at the point of attachment with the hyphae of 

 the host; sporangiophores creeping, verticillately branched, ending in a 

 long, sterile, pointed tip, the branches short with sterile tips, bearing on 

 the swollen portion large numbers of single conidia. 



Etymology: Greek x mT v, hair, and K.la<Scov, branch. 



Chaetocladium l>rel"eldii Van Tiegh, & LeMon. Ann. Sc. Nat. Bot. 5, XVII., 



342. 1873. 

 Characters of the genus; conidia globose or globose-elliptical, smooth, color- 

 less, 2-5 fi. 



