230 



poisonous effect of the grass is enhanced in times of drought. One 

 writer states that the grass is dangerous only in the green state, 

 and that if the same grass is cut and dried and used for fodder, it 

 has no injurious effect. This may be due to the destruction of the 

 glucoside or the emulsin, or both, by the drying of the ^rass with- 

 out their coming into contact with each other, but it is possible 

 that the grass was not cut till near maturity, that is to say after 

 the disappearance of the prussic acid yielding glucoside. 



w. n. T. 



Derris involuta* — This species has been identified in the Kew 

 Herbarium with 7). oligospervia, K. Schum. et Lauterb., by Mr. 

 S. T. Dunn, who is preparing a revision of the genus; and the 

 reduction was accepted in Bot- Mag. t. 8530. During a recent 

 visit to Berlin, however, the writer had the opportunity of com- 

 paring D, involuta with the type of D. oligospermay and the dif- 

 ferences then observed led to the conclusion, in which Dr. Harms 



two 



The 



following notes may serve to prevent them from being confused in 



the future. 



Leaflet 



olig 



late at the apex; midrib and lateral nerves impressed on the upper 

 surface, much raised on the lower; lateral nerves very oblique, the 

 iniddle ones running for more than half the length of the leaf 

 before curving away from the margin; reticulation not evident on 

 the upper surface. — Native of New Guinea. 



Le 



Derris involuta, Sprague. 



Ma 



truncate and indistinctly mucronulate at the apex; midrib and 

 lateral nerves slightly raised on the upper surface, 



more 



raised on the lower; lateral nerves less oblique than in D. oligo^ 

 sperma, the middle ones running for less than half the length of 

 the leaf before curving away from the margin; reticulation 

 evident on the upper surface. — Native of Queensland and New 

 South Wales. 



The comparison has been confined to the leaves, as the flowers 



petraa 



T. A. S 



1 



Botanical Magazine for August.— The plants figured are 



Cyrtosperma Johnstoni, N. E. Brown (t. 8567) ; Meconopsis rudis, 

 Prain (t. 8568) ; Rosa i^etipoda, Hemsl. and E. H. Wils. (t. 8569) ; 

 Zingiber Mioga, Roscoe (t. 8570), and Cotoneaster Franchetii, 

 Bois (t. 8571). 



Tlie Cyrtosperma is an Aroid introduced from tlie Solomon 

 Islands by the late Mr. William Bull, who distributed it under the 

 name of Alocasia Johnstoni, It is a very distinct plant and of 

 considerable ornamental value, with its red-veined, arrow-shaped 

 leaves.^ Petioles and peduncles are spiny, and the erect spathe» 



'' * :h is about 6 inches lone-, is dark violet and slightly polished 



y whitish-green faintly flushed with 



