MICROSCOPIC ALG.E AND FUNGI. 



203 



are the more important of these essays that have yet appeared, 

 and should be attentively studied by all who are desirous of 

 becoming acquainted with the matter. 



The present work is, in fact, a collection of shorter essays 

 having more or less direct reference to the same subject, and 

 will be found to contain a vast amount of important and 

 interesting information. 



The subjects treated of are — 



1. Ou the relation of the microscopic Fungi to the microscopic Algce. 



2. On Chytridium, and some allied genera. 



3. Observations on Oonimn pectorale, and the Volvocina in general. 



4. On the propagation of Hydrodictyon utricidatum, together with 



some remarks on " swarm-cells " in general. 



5. On the germination of Zygnema and Anabcena. 



These papers are illustrated by figures of 



Anthophysa MilUcri. 



Zooglcea {yibrki) termo. 



SpirnUna plicatiUs (^Spirochicte, p., 



Ehr.) 

 Spiridina Jenneri. 

 Synedra putrida, n. s. 

 Chlamydomonas hyalina ( Polytonid 



uvella, Ehr.) 

 Chytridium globosum, A. Bi'aun. 

 Peronium aviculare, Cohn. 

 AcMya proUfera. 

 Spirogyra nitida. 



Zygnema stelUnum . 

 Closterium Lunula. 

 Mougeotia genuflexa ? 

 Anabcena intricata ? 

 AcMya capitulifera. 

 Cldamydococcus pliivialis. 

 Oonium, pectmrde. 

 Chlamydomonas pulvisculus. 

 Hydrodictyon utricidatum. 

 CEdogcniium capillare. 

 Cladophora glomerata (monstrous 

 spores of). 



1. On the relations of tlie microscopic Fungi to the micro- 

 scopic Algae. 



The result of his study of the lowest forms has led Dr, 

 Cohn to the conclusion, that no sufficient reasons derived from 

 morphological and developmental considerations exist for the 

 separation of the Algae from the Fungi. Though the distinc- 

 tion between the Thallophytes and Cormophytes of Endlicher 

 is sufficiently definite, the three classes into which the former 

 have, since Linnaeus, been subdivided, viz., the Algae, Fungi, 

 and Lichens, are by no means so well defined as, for instance, 

 the Mosses from the Ferns, or the Equisetaceae from the 

 Lycopodiaceae. It would seem as if the multitudinous class 

 of Thallophytes constituted, or^ganolocjically, but a single 

 indivisible kingdom, and that the above three provinces 

 were characterized merely by the more or less developed, and, 

 it must be confessed, widely different forms, and in no way 

 by any intrinsic difference of type in the vegetative or repro- 

 ductive organization. 



The Algae, as usually understood, like most other plants, 

 are capable of appropriating, by an innate power, the materials 



