504 



MONTGOMERY. 



[Vol. XV. 



Form. 



A Single 

 Nucleolus. 



More than One Nu- 

 cleolus, All Alike. 



Nucleolus and 

 Paranucleolus. 



r Neritina 



! Doto 



[ Montagua 



Tellina 



Helix 



Limax 



Arion 



Doris 



Aeolidia 



Amphorina 

 t Paludiiia 

 r Anodonta 



Unio 



Mytilus 



Pholas 



Cyclas 



Distaplia 



Phallusia 



Botryllus 



Clavelina 



Ciona 



Styelopsis 



Ascidia 



* (Blochmann) 



* (mihi) 



* (Plainer) 



Tunicata. 



* (Davidoff) 



* (Bergh) 



* (Pizon) 



* (Seeliger) 



Vertebrata. 



(mihi) 



(O. Hertwig) 



* (Mark) 



* (Plainer) 



(Lonnberg) 



* (Trinchese) 

 (Leydig) 



* (Flemming) 



* (Hessling) 



* (Lonnberg) 



* (List) 



* (Stepanoff) 



* "1 



^ !► (Flodenis) 



* J 



* (O. Hertwig) 



