MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 



123 



and a half centimeters in thickness. 

 It remains of about the same width 

 and thickness nearly to the irregu- 

 larly conical end. The tentacles 

 of the spadix have the' same rela- 

 tive arrangement as those of the 

 antispadix. Each is greatl}' in- 

 creased in size, with the exception 

 of the fourth tentacle, which is 

 but little larger than its repre- 

 sentative in the antispadix. 



The cirrus of the first tentacle 

 has become an enormous conical, 

 fleshy organ. (Fig. 15.) The cirrus 

 of the second has liecome flattened 

 as well as enlarged, and ))ears num- 

 erous rows of small glands upon 

 one surface. (Fig. l(i.) The cir- 

 rus of the third is also flattened at 

 its tip. and shows upon its ventral 

 side many rows of tine pores. 

 (Figs. 17 and 18.) 



The sheaths of the first, 

 second, and third tentacles are 

 completely fused and have de- 

 veloped in accordaiK'c with the 

 cirri, and now form a structure 

 which Vayssiere has proposed to 

 call the sheath of the spadix. 

 (Figs. 13 and 14.) 



There is a groove in the outer 

 side of the sheath of the spadix, 

 between the second and third cirri. 

 , into which the tip of the fourth 

 cirrus is pressed. (Fig. li. ) The 

 tip of this cirrus is overlapped by 

 a broad flap, which corresponds to 

 the smaller flap noticed upon the 

 outer side of the antispadix. The 

 base of the fourth tentacle lies 

 within a notch in the sheath of the 

 spadix and is not covered. Its 

 own sheath is .short and is free 

 from the sheath of the spadix for 

 a short distance only. In this 

 respect the fourth tentacle of the 

 spadix differs quite noticealily 

 from the corresponding tentacle 

 of the antispadix. 



Upon the outer side of the 

 sheath of the spadix, and near its 

 tip, is a large circular glandular 

 area, slightly raised al)ove the 

 general surface. (Fig. l-i, G.) 

 The glandular area extends out 



Text-fig 5. — Transverse sections of the spadix at successive levels. 



X, nearest the tip; D, nearest the base of the organ; 1, first cirrns; 2, second cirnis; 

 ;J, third cirrus; 4, f<nirfh cirrus; S, sliiin- gland of spadix sheath. 



