TEMPSKYA. 149 



usually included under that name are only incomplete pieces of 

 fern stems, any attempted diagnosis would be of little value. 

 Solms-Laubach 1 speaks of certain forms of Rachiopteris occurring 

 in the " Tempskya condition" ; and this probably means that they 

 are imbedded in a felted mass of adventitious roots. As will be 

 shown in the sequel, certain species previously referred to this 

 genus have been proved by the examination of more perfect 

 material to be referable to other and more precisely denned 

 genera. It will be well for the present to retain Corda's term, 

 if we regard it as implying a particular manner of preservation 

 rather than any well- denned generic characters. Used in this 

 provisional sense, Tempskya includes such specimens of tree-ferns 

 as consist in the main of felted masses of adventitious roots, 

 with occasional petioles associated with them, and which are 

 without any distinct vascular cylinder. 



Yelenovsky has made some important additions to our know- 

 ledge of these Tempskya, forms, which will be referred to under 

 T. Schimperi, Cord. 



I am indebted to Prof. Stenzel, 2 of Breslau, for certain im- 

 portant suggestions as to the nature of the genus Tempskya. He 

 points out that this term is occasionally used in the case of 

 specimens which consist simply of roots without any trace of 

 stems; he mentions the receipt of such a " Tempskya" from the 

 late Dr. Stur, and compares the structure of the roots to that 

 characteristic of Protopteris punctata or P. microrhiza. This form 

 of Tempskya, as Stenzel adds, does not conform to the original 

 description by Corda, in which reference is made to petioles asso- 

 ciated with numerous roots. 



In referring to Corda's opinion that Tempskya probably repre- 

 sents a portion of a tree-fern stem above the actual stem apex, 3 

 Stenzel justly points to the great masses of roots in different 

 species of this genus as a fatal objection to such a view. Stenzel 

 adds that Corda's specimens must have been pieces from the lower 

 part of a stem ; but, judging by the great thickness of the root- 

 mass on one side of the stem of T. pulchra and T. Schimperi as 

 figured by Corda, 4 there must have been a considerable length of 



1 Fossil Botany, p. 159. 



2 Letter, Dec. 1893. 



3 Flor. Vorwelt, p. 81. 



* Ibid. pi. Iviii. fig. 1 ; pi. lix. fig. 1. 



