THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL. 



Vol. XIV. 



SEPTEMBER, 1893. 



No. 9. 



Pcnicillium and Some Other Funjri. 



liv HKNRY LESLIK OSBORN, 

 ST. PAIL, MINN. 



WITH KUIINTISPIECK. 



The study of the fungi is so very easy for any one who is de- 

 sirous of ap}tlying liis niicroscoi)e to the discovery of facts in 

 nature that surely it will be worth while to devote some space 

 to an account of a few of them. Moreover, there are many of 

 tliem of the utmost practical interest to man, being intimately 

 connected with many of the most necessary of his operations 

 Thus the baker, the brewer, the dairy-man, are directly at the 

 mercy of fungi. The agriculturi.st is often hindered in his i)lans 

 by their growth, while in other cases his plans are helped. 

 The doctor has in many of his patients to contend with the 



EXFL.\NATION OF THE PLATT-:. 



1. — I'enu'illitnu, 



1. Tlie niyceliiim ofii young colony of Peiiicil- 

 lium, — growth from the 8iH>re of aliout 

 three diiys. 



2. The til« of a sulimerged hypha. Note the 

 scarcity of vacuoles. 



:5. Tip of a branching hypha. 



4. Lower portion of a submerged liypha, 



showing vacuoles and the cross-wall.-i. 

 .'p. Lower portion of a submerged hypha, 



Nhowing the lateral hranching. 

 ti. Kilateriil brandling in a submerged hypha. 



7. Lateral branch to show it.-* relation to the 

 parent hypha as a prolongation of it. 



8. An aerial hypha bearing the basidia (ba), 

 sterigmata (st), and the numerous conidia 

 in rows, 



9. \ conidium in the act of germinating, 

 sliowing the young hvpha emerging. 



2.— .W»...r. 

 1(1. The entire plant-lKxIy , showing the mycel- 

 liuni below the unbranched and iinicelu- 

 lar aerial hyiihie and their terminal spor- 

 angia (sp). 

 tl. More enlarged view of the mycelium show- 

 ing till' pr(itopla.-<m and the vacuoles. 

 12. .\ yonng s|Hiranginm showing the proto- 

 plasm li>-f(ire spore formation. 



13. A more highly magnified view of a part of 

 Fig. 12, showing the greatly vacuolateil 

 character of protoplasm. 



-14. The germinating Zygospore, showing the 

 two conjugating hypha- (hy-1) and (liy-2), 

 and the germinating sjiore with the third 

 hy|)ha (.hy-:l). 



3. — Cyflojiug candidus. 



1."), a. The hypha (hy) surrounded by the tis- 

 sue of the host showing the haustotia (h), 

 the cell-wall of the host cell, the proto- 

 plasm of this cell (p. u). 



1'), b. The conidia on their parent hypha. 



15, c. The conidium with its contents dividing. 



l.*!, d. The escaping spores of the conidial 

 generation. 



l.'i, e. The later stage of the process. 



1.5, f. The motile swarm-spore of Cystopna. 



15, g. The spores germinating on the stoma 

 of a host plant 



15, h. The sexual leproduction by means of 

 theantheridia (an), and the oogonium (og). 

 The oosphere (os) is shown and the union 

 between the oosphere and the antheridium 

 is indicated. 

 All these figures are from nature except those 



of Cystopus. 



