Miscellaneous. 135 



which perforate the latter. These tubes, which are opeu at the 

 extremity, play the part of suckers, which pump in the fovilla and 

 transmit it through the canals to the ovary. After fecundation, the 

 perforated poUen becomes dried up, whilst the stigma becomes folded 

 upon itself and withers. 



Consequently in the Graminese two principal phenomena occur, 

 which are witnessed only in this family : — 



1. The elongation and expulsion of the filaments of the stamens. 



2. Pecundation by the perforation of the pollen. 

 These do not occur without reason. 



The seed, the result of fecundation, must occupy when perfectly 

 developed, the whole chamber formed by the union of the two 

 valves. Now the stamens occupy two-thirds of this space, and by 

 their volume they would obstruct the growth of the seed : they 

 must be expelled ; and hence the elongation of the filaments, and 

 the existence and the utility of the alimentary glands. 



As the fecundation is instantaneous, it is necessary that the fovilla 

 should instantaneously penetrate to the ovary through the stigma, 

 the existence of which only lasts during the moment of fecundation ; 

 hence the structure of the stigma, and the phenomenon of the per- 

 foration of the pollen. 



All the facts that I have just indicated may be very easily ob- 

 served in our cereals and the grasses of our meadows. To see the 

 details of the fecundation, it is only necessary to spHt the outer 

 valve longitudinally ; by separating the two parts of this valve, we 

 expose the organs of fecundation enclosed in the two curtains of the 

 inner valve, and the warmth of the breath or a ray of the sun is 

 sufiicient to induce the phenomenon of fecundation. 



The natural hybridization of the Graminese is impossible, from 

 the exact closure of the space or chamber containing the oi'gans of 

 fecundation. — Compies Bendus, June 21, 1869, tome Ixviii. p. 1486. 



On a Tree-Frog in New Granada which secretes a Poison employed 

 by the Indians to poison their Arrows. By J. Escobab. 



This tree-frog appears to belong to the species called PhyUohates 

 melanorhinus. It is known in the country by the names of Ranilla 

 roja or rojiga. During life it is of a red tint shaded with Naples 

 yellow, and consequently rather yellowish red, like certain oranges, 

 the colour of which approaches that of the citron. The yeUow pre- 

 dominates when the animal has been some time in alcohol. There 

 are two varieties — one in which the belly is black, and another in 

 which it is of the same colour as the upper parts. 



The poison is furnished by the dorsal region. It does not appear 

 to possess its properties completely unless it is collected at the moment 

 when the animal, still living, secretes it. To cause its secretion, 

 they introduce into the mouth of the frog a small wooden spatula, 

 and, taking great precautions in order not to produce injuries which 

 would cause death too rapidly, push it in so as to cause great suf- 

 fering, under the influence of which the whole upper surface of the 



