46 Parasitical Connection of LatJir<^^a Squamm^id, 



organisation and mode of growth. This discovery is the 

 subject of a luminous paper, illustrated by eighteen figures 

 from Mr. Bowman's pencil, in the sixteenth volume of the 

 Linnean Society's Transactions, 



In his highly interesting paper, the author details, with 

 much clearness and precision, the result of his investigations 

 on the organisation of this singular plant ; and as they ex- 

 hibit some striking exceptions from the general laws of vegeta- 

 ble physiology, not hitherto known, we shall present them to 

 our readers as fully as our limited space will allow, and illus- 

 trate them by several of the original drawings confided to us 

 by the liberality of the council of the Linnean Society. 



It has long been known, that every part of the Lathrae^a 

 Squamaria, except the flower-stems, is at all times strictly 

 subterraneous ; but we are not aware that any botanist has 

 hitherto detected the nature of its parasitical connection, or 

 the anomalous structure of its leaves. It may indeed be 

 said to set the ordinary laws of vegetable life at defiance, 

 even in its infancy ; for no sooner has the embryo "plant 

 emerged from its cotyledons, than, instead of seeking the 

 surface of the soil, it takes a downward direction, till it comes 

 in contact with the roots by which it is nourished, after which 

 it spreads horizontally among them. Its real root, it appears, 

 is spindle-shaped and branched, terminating in forked fibres ; 

 which however do not draw moisture from the soil in the 

 ordinary way, but are furnished at and near their extremi- 

 ties with very minute tubers, which fix themselves on the 

 roots of trees and extract their juices. Similar tuberiferous 

 fibres are copiously produced on the subterraneous stem be- 

 tween the imbricated scales. The tubers, though not larger 

 than a small pin head, are exceedingly numerous, hemispheri- 

 cal, and of a succulent and tender texture. When fixed on 

 the root, they throw down a funnel-shaped process or tap, 

 which penetrates through the cortical layers into the al- 

 burnum (where the sap is in the greatest energy), and com- 

 so ^J^^^ municates with a system of vessels 



of a jointed or beaded structure. 

 These vessels traverse the substance 

 of the tuber, and convey their stolen 

 contents along the connecting fibre 

 for the support of the parasite. The 

 annexed figure (Jig. 30.) is a per- 

 pendicular section of a tuber, highly 

 magnified, showing the insertion 

 of its tap-shaped base into the al- 

 burnum. 



