76 Miscellaneous. 



nifest, and requires no recommendation, to judge from the results 

 which have already ensued. His own efforts with respect to coal had 

 never been attended with success, and he therefore considers this 

 method as a most useful and important discovery. He further stated 

 that the clearness of the specimens (which were, it was to be re- 

 gretted, not numerous) communicated by M. Schulz had astonished 

 him, and, as might have been expected, had immediately been at- 

 tended with a result. Prof. Ehrenberg had during many years 

 brought before the Academy descriptions of the parts of plants (con- 

 taining silica) which are found in marshy soils of all zones and in the 

 infusorial deposits, and had likewise alluded to their origin from re- 

 cent plants. This group, called Phytolitharia, had been as it were 

 classified by him into eleven genera. Of these eleven genera only 

 one is found in several forms in the purified siliceous ash of the coal 

 forwarded by M. Schulz, namely the genus Lithostylidium, which 

 contains regular siliceous nuclei of cells of plants. Lithodontia, or 

 marginal teeth of grasses, Lithodermatia, or epidermis of plants 

 (Equisetacea, Arundinacea), could not be distinctly recognised, al- 

 though the presence of the latter may be presumed. Other nega- 

 tive results were also particularly remarkable, namely the absence 

 of all Lithasterisci, Lithospheera, Spongolites, &c. &c., otherwise so 

 frequent. Finally, no trace of infusoria possessing a siUceous shell 

 was found, notwithstanding the most careful investigation. 



He concluded by expressing a conviction that a rapid development 

 of our knowledge on this subject would, now that a method had been 

 discovered, undoubtedly take place, and a wish that this may be the 

 commencement of its study. 



On the Tendrils of the Cucurbitaceae. By M. J. Payer. 



In organographical researches it is sometimes necessary to examine 

 comparatively the same organ, not merely in plants of the same fa- 

 mily, but likewise in the same plant at various periods of its exist- 

 ence, and, if necessary, to have recourse to anatomy. It is from 

 having neglected these two modes of investigation that all botanists 

 who have studied the nature of the tendrils of the Cucurbitacece have 

 either been completely mistaken, or have perceived the truth but in 

 a very indistinct manner, and without being able to demonstrate it. 



There are many plants in which fibro-vascular bundles are de- 

 tached at three different points of the circumference of the cylinder 

 constituting the medullary sheath, generally at one and the same 

 height and at a little distance from the origin of a leaf : these bun- 

 dles traverse the herbaceous envelope and pass into the pulvinus 

 (^coussinet) of that leaf. There, sometimes all three enter the pe- 

 tiole, sometimes only one of them, — the central one, the two lateral 

 ones continuing the nervation of the two lateral stipules. Now, if 

 the lower leaves of the cultivated melon be examined, no tendril will 

 be found to exist at their side*; it will be seen that the three fibro- 



* This fact may be generalized, for it results from a large number of ob- 

 servations which I have made, that plants with tendrils, of whatever kind, 

 jjxever present tendrils at their lower extremity. 



