Ceap. III. BIGNONIACE^. 101 



which sometimes wholly enveloped and concealed the 

 hooks themselves. The surfaces of these balls secrete 

 some viscid resinous matter, to which the fibres of the 

 flax, &c., adhere. When a fibre has become fastened 

 to the surface, the cellular tissue does not grow 

 directly beneath it, but continues to grow closely on 

 each side; so that when several adjoining fibres, 

 though excessively thin, were caught, so many crests 

 of cellular matter, each not as thick as a human hair, 

 grew up between them, and these, arching over on 

 both sides, adhered firmly together. As the whole 

 surface of the ball continues to grow, fresh fibres 

 adhere and are afterwards enveloped; so that I have 

 seen a little ball with between fifty and sixty fibres 

 of flax crossing it at various angles and aU embedded 

 more or less deeply. Every gradation in the process 

 could be followed — some fibres merely sticking to 

 the surface, others lying in more or less deep furrows, 

 or deeply embedded, or passing through the very 

 centre of the cellular ball. The embedded fibres are 

 so closely clasped that they cannot be withdrawn. 

 The outgrowing tissue has so strong a tendency to 

 unite, that two balls produced by distinct tendrils 

 sometimes unite and grow into a single one. 



On one occasion, when a tendril had curled round 

 a stick, half an inch in diameter, an adhesive disc 

 was formed ; but this does not generally -occur in the 

 case of smooth sticks or posts. If, however, the tip 

 catches a minute projecting point, the other branches 

 form discs, especially if they find crevices to crawl 



