CARNIVOROUS PLANTS WITH ADHESIVE APPARATUS. 153 



the lamina, especially along the midrib, there are pointed hairs, whilst a great 

 number of glands, some larger and some smaller, occur from the midrib to nearly 

 the middle of each lobe. The larger glands are discoid, and not unlike the sessile 

 glands on the leaves of Pinguicida. They consist of four median cells with 

 twelve others grouped round about them, and are borne upon a very short stalk. 

 The small glands are few-celled, being usually composed simply of a capitate-cell 

 resting upon a short foot-cell (see fig. 28^). Towards the incurved margin of the 

 lamina are displayed scattered stellate hairs, i.e. groups of cells so arranged as 

 to present the appearance of a St. Andrew's cross when seen from above. 



If minute animals or Diatomacese, especially species of Navicula, whilst 

 swimming about in the w^ater, touch the upper surfaces of the lobes set at right- 

 angles — in particular, if the hairs in the middle are stroked as they creep 

 by— the two lobes shut together quickly in the same way as those of Dioncea, and 

 the animal or Navicula, as the case may be, is then enclosed in a cage between 

 two somewhat inflated walls. The possibility of an attempt on the part of the 

 captive to escape by the place where the margins of the lamina meet is met by the 

 circumstance that the edges of the incurved margins are furnished with sharp 

 indentations turned towards the interior of the cavity enclosed between the lobes 

 (see fig. 28 5). 



Amongst the prisoners we find the same company as in the traps of Utricularia, 

 namely, small species of Cyclops, Daphnia, and Cypris, larvae of aquatic insects, and 

 not infrequently also species of Navicula and other free and solitary Diatomacese. 



How the prey is killed and digested has not yet been ascertained. It does not 

 in any case take place so quickly as in Dioncea, for instances have been seen of 

 animals still living in their prison six days after being caught. But, at last, move- 

 ments and vital actions cease, and if after a couple of weeks the two lobes of the 

 lamina are pulled apart, the only contents to be found are shells, bristles, rings, and 

 siliceous skeletons, whilst everything soluble has vanished, having evidently been 

 absorbed. 



Very similar to the species distributed through Southern and Central Europe 

 are Aldrovandia australis, a native of Australia, and Aldrovandia verticillata, 

 inhabiting tropical India. The fact that the remains of small aquatic beetles 

 and other creatures have been found within their closed laminse, leads us to the 

 conclusion that they act as entrappers of animals in the same way as Aldro- 

 vandia vesiculosa. 



CAENIVOROUS PLANTS WITH ADHESIVE APPARATUS. 



The forms constituting the third section of carnivorous plants neither have pit- 

 falls nor move in response to the contact of animal matter, but the leaves act as 

 motionless limed twigs, their glands having the power of pouring out sticky sub- 

 stances to capture prey and juices to digest it, being able besides to re-absorb the 

 albuminoid compounds dissolved. The most striking representative of this section, 



