cohol , v/I;ich decalcifins aa v/ell as stains. The Tigiures 

 have all been rlravm with the aid of a Zeiss camera lucida. 

 In some car.-^s, as in the series of transverse sections of 

 the adult (firrs. :13-Zb) , they have been "touched up" af- 

 terv/ards. However, in no case have thejr been essentially 

 modified and are in no wise diagrams. The figures of ad- 

 ults have been made from specimens about ten centimeters 

 long, vfhich I had raised, and v^hich were killed perfectly 

 extended. The siphons, however, have been filled in from 

 life, or from preserved specimens tliat had been narcotized 

 before killing. In larger specimens the body as a vfhole , 

 and the various orr;ans are somewhat more elongated, but 

 the relations remain the same as in yoi^nger specimens. 



