CHAP. XIV. ALDROVANDA VESICULOSA. 821 



CHAPTEE XIV. 



ALDROVANDA VESICULOSA. 



Captures crustaceans Structure of the leaves in comparison with 

 those of Dionsea Absorption by the glands, by the quaclrifid pro- 

 cesses, and points on the infolded margins Aldrovanda vesiculosa, 

 var. australis Captures prey Absorption of animal matter 

 Aldrovanda vesiculosa, var. verticillata Concluding remarks. 



THIS plant may be called a miniature aquatic Dionaea. 

 Stein discovered in 1873 that the bilobed leaves, 

 which are generally found closed in Europe, open 

 under a sufficiently high temperature, and, when 

 touched, suddenly close.* They re-expand in from 

 24 to 36 hrs., but only, as it appears, when inor- 

 ganic objects are enclosed. The leaves sometimes 

 contain bubbles of air, and were formerly supposed to 

 be bladders ; hence the specific name of vesiculosa. 

 Stein observed that water-insects were sometimes 

 caught, and Prof. Cohn has recently found within the 

 leaves of naturally growing plants many kinds of 

 crustaceans and larvae.f Plants which had been kept 

 in filtered water were placed by him in a vessel con- 



* Since his original publication, cliioccioline are fresh-water mol- 



Stein has found out that the irri- luscs. It would be interesting to 



tability of the leaves was observed know whether their shells are at 



by De Sassus, as recorded in all corroded by the acid of the 



' Bull. Bot. Soc. de France,' in digestive secretion. 



1SGI. Uelpino states in a paper f I am greatly indebted to this 



published in 1871 (' Nuovo Ciior- distinguished naturalist for having 



nale Bot. Ital.' vol. iii. p. 171) sent me a copy of his memoir on 



that " una quantita di chioccio- Aldrovanda, before its publica- 



line e di altri animalcoli acqua- tion in his ' Beitrage zur Biologie 



tici" are caught and suffocated der Pflanzen,' drittes Heft, 1875, 



by the leaves. I presume that p. 71. 



