114 M. L. R. Tulasne on the Reproductive Organs 



XIV. — On the Reproductive Organs of the Lichens and. Fungi 

 (First Part). By M. L. R. Tulasne*. 



Among the various products originating on the thallus of the 

 Lichens, the black points to which the attention of botanists has 

 been recently directed by M. Itzigsohn, are not those least worthy 

 of thorough examination. Long known to lichenographers, these 

 points have been taken sometimes for parasitic Fungi of the order 

 Pyrenomycetes, sometimes for anomalous fructifications, or even 

 for peculiar species of Lichens. With regard to their organi- 

 zation, M. von Flotow, who seems to be the last who has spoken 

 of them, appears to consider them as little utricles filled with a 

 mucilage in which swim cylindrical corpuscles of extreme tenuity, 

 animated with a molecular motion. In his eyes these corpuscles 

 are spores in a rudimentary condition, destined however subse- 

 quently to become perfect reproductive organs. M. Itzigsohn, 

 on the other hand, has been induced to regard the points in 

 question as antheridia analogous to those of the Mosses and He- 

 patiese, and the corpuscles they contain as animalcules endowed 

 with a movement of translation. He affirms that these cor- 

 puscles become developed, like the spermatozoids already known, 

 within lenticular cells seemingly imbedded in the green tissue 

 of the Lichen. Like MM. Kiitzing and Von Flotow, I have not 

 been able to witness the vital motion attributed to these cor- 

 puscles, even by employing the means recommended for the pur- 

 pose ; and far from seeing them originate in special cells like the 

 spermatozoids of the Muscinese, I have satisfied myself that they 

 are developed on the surface of a basidigerous hymenium, and owe 

 their origin to an acrogenous vegetation. 



Whatever resemblance there may be, at first sight, between 

 the black or brown points in question and the antheridia of the 

 stemless Jungermannise for instance, — that a kind of mucilage, a 

 white, gray, or brownish pulp is poured out by both, — the ele- 

 ments of this substance and the structure of the organ in which 

 it is elaborated are unlike in the two cases. In the Lichens, the 

 pulp effused from the thallus is composed solely of linear bodies 

 which are very short and slightly curved, or more elongated and 

 thin, either strongly curved into an arc or more or less flexuous ; 

 but these corpuscles never appear to present cilia or appendages 

 of any kind, and their confused movements do not differ from 

 the molecular trembling described by Mr. Brown; in a word, 

 they do not possess the characters which distinguish those sin- 

 gular beings engendered in antheridia properly so-called. 



They differ no less, as I have said, in their mode of develop - 



* Translated from the Comptes Rendus for March 24, 1851. 



