210 DKOSERA ROTUNDIFOLIA. CHAP. X. 



or small group of glands through the bade to the 

 other tentacles more readily and effectually in a 

 longitudinal than in a transverse direction. 



As long as the glands remain excited, and this may 

 last for many days, even for eleven, as when in contact 

 with phosphate of lime, they continue to transmit a 

 motor impulse to the basal and bending parts of their 

 own pedicels, for otherwise they would re-expand. The 

 great difference in the length of time during which 

 tentacles remain inflected over inorganic objects, and 

 over objects of the same size containing soluble nitro- 

 genous matter, proves the same fact. But the intensity 

 of the impulse transmitted from an excited gland, 

 which has begun to pour forth its acid secretion and 

 is at the same time absorbing, seems to be very small 

 compared with that which it transmits when first ex- 

 cited. Thus, when moderately large bits of meat were 

 placed on one side of the disc, and the discal and sub- 

 marginal tentacles on the opposite side became in- 

 flected, so that their glands at last touched the meat 

 and absorbed matter from it, they did not transmit 

 any motor influence to the exterior rows of tentacles 

 on the same side, for these never became inflected. 

 If, however, meat had been placed on the glands of 

 these same tentacles before they had begun to secrete 

 copiously and to absorb, they undoubtedly would have 

 affected the exterior rows. Nevertheless, when I gave 

 some phosphate of lime, which is a most powerful 

 stimulant, to several subrnarginal tentacles already 

 considerably inflected, but not yet in contact with 

 some phosphate previously placed on two glands in the 

 centre of the disc, the exterior tentacles on the same 

 side were acted on. 



When a gland is first excited, the motor impulse is 

 discharged within a few seconds, as we know from the 



