CHAP. XVIII. STRUCTURE OF THE BLADDERS. 



433 



just enter the bases of the bladders ; but they do not 

 bifurcate and extend up the dorsal and ventral sur- 

 faces, as in the previous species. 



The antennae are of moderate length, and taper to a 

 fine point ; they differ conspicuously from those before 

 described, in not being armed with bristles. Their 

 bases are so abruptly curved that their tips generally 

 rest one on each side of the middle of the bladder, but 



FIG. 27. 



(Utricularia numtana.) 

 Bladder; about 27 times enlarged. 



sometimes near the margin. Their curved bases thus 

 form a roof over the cavity in which the valve lies ; 

 but there is always left on each side a little circular 

 passage into the cavity, as may be seen in the drawing, 

 as well as a narrow passage between the bases of the 

 two antenna?. As the bladders are subterranean, had 

 it not been for the roof, the cavity in which the valve 

 lies would have been liable to be blocked up with earth 



