THE ANNALS 



AND 



MAGAZINE OF NATURAL HISTORY. 



[THIRD SERIES.] 



" perlitora sparglte museum. 



Naiades, et circilm vitreos considite foiites : 

 Pollice virgiiieo tciicros h1c carpite flores : 

 Floribus et pictum, divie, replete canistrum. 

 At vos, o Nymphs Craterides, ite sub undas ; 

 Ite, recurvato variata corallia trunco 

 Vellite muscosis e rupibus, et mihi conchas 

 Ferte, Deae pelagi, et pingui conchylia succo." 



N. Parthenii Giannettasii Eel, 1. 



No. 1. JANUARY 1858. 



I. — On the Propagation of the Desmidiese a?i£? Diatomeae. 



By W. HOFMEISTER*. 



j\ UMEROUS as the researches have been, published during the 

 last ten years f, on the conjugation of the Desmidieffi and Dia- 

 toniese ; satisfactorily as these have in some cases made out the 

 course of conjugation, the behaviour of the mother-cells, and 

 the formation of the conjugation-cell, — yet little is certainly 

 known respecting the subsequent fate of the spores produced 

 by conjugation, especially in the Desmidiese — a natural con- 

 sequence of the difficulties of the observation, in which the 

 inquirer is dependent almost more than anywhere else upon 

 accident. The following pages will furnish information on this 

 point, in reference to two, confessedly very nearly allied species 

 of Desmidiese. 



Cosinarium tetraophthalmum, Kg., collected in May 1853, with 

 many other Desmidiere, in a little pool abounding in such or- 



* Bericht. K. Sachs. Gesellsch. d. Wissensch. Feb. 21, 1857. Translated 

 by Arthur Henfrey, F.R.S. &c. 



t Thwaites, Ann. Nat. Hist. 1847-49. Ralfs, British Desmidieae, Lon- 

 don, 1848. Braun, Verjungun^ an der Natur (1849) (Ray Translation, 

 1853, p. 281). Smith, British Diatomacejc, ii. London, 1856. 

 Ann. ^- Mag. N. Hist. Ser. 3. Vol. i. 1 



