OBSERVATIONS ON POLYZOA. 



227 



sixty. The statoblasts vary between .199 m. m. in 

 breadth by .333 m. m. in length ; .233 m. m. in breadth 

 by .349 m. m. in length. The proportions are in equal 

 parts from 6 by 10 to 6 by 12, 6^ by 11 J, and 7^ by 10^ ; 

 annulus varies from f at the sides to f at the sides and f 

 at the ends. 



being 



large 



PECTINATELLA. 



Coencecium without cells, the branches 

 lobes with the polypides on the upper side ; naked above, 

 with the ectocyst gathered below into a thick common 

 base for the colonies. Invaginated fold almost obsolete. 

 Statoblasts with sjpinous annuli, extremities rounded. 



Pectin ATELLA magnifica. 



The polypides are arranged on the lobes ; sometimes 

 in single, but generally in double rows, placed alternately. 



The ectocyst is of 

 great thickness at the 

 centre, and may be 

 from four to eight 

 inches in depth ; arms 

 about as long as the 

 evaginable tube of the 

 polypide. 



Tentacles number 

 from sixty to eighty- 

 four. Lower part of 

 these and the mouth 

 parts are crimson. 



Statoblasts vary 

 from .8 m. m. in 

 breadthto .9 m. m. in 

 length. The propor- 

 tions in equal num- 

 bers are as follows : 24x37 



24 bv 27, or 26 bv ^^^- ^''' ^'^'^"* Mystic Pond, near Cambridge, 

 c\n c\rr oo c>c ^ Mass. Although usually the anjQuhis Oil the lower 

 27, 27 by 2o, 28 by side presents a broader surface, as in Pl. 10, rigs. 

 00 onv. QA Qr\ V. ^ ^^'^ *' ^^^^ ^® often so narrow tliat when meas- 

 Zy, ZJ Dy OU, OO Dy ured from above there is no appreciable differ- 

 on ence. [The lateral view of the statoblast in PI. 

 "'-'• 10 is correct, and therefore not given here.] 



