618 



COMPA RA TIVE ANA TOMY 



', 6 



Tylaster, 297 

 Tylodina, 10 



UlNTACRINUS, 309 



Umbrella, 10 

 Umbretlidfv, 10 

 Uucmi, 182 

 Unio, 17 



Margaratlferus 

 35 



,, pinctorum, 17 

 Unionidce, 17 

 1'iii induce, 50 

 Uniophora, 299 

 Urechinus, 298 

 Urns, ciliated, 437 

 Utriculus, 180 



!, S 



\'nij!n uliifi, 45 

 Valvaster, 299 

 Valvatidce, 6 

 Veliger, larva, 1, 257 

 Velum, 250 

 \'<'in-f(icea, IS 

 Vc nericardia, 17 

 Ven&ridce, IS 

 Venus, 18 



17, 



Vermetus, 108, 248 

 Vertebra] ossicles (Oph. ), 356 

 Verticordiii/tt; 51 

 Vitrinn, S 

 Volutuht', 6 

 Vulsella, 17 



WACHSMUTH and Springer's rule, diagram, 



374 

 Wandering cells (amcebocytes) (Echin.), 



415 

 Water lung (Hoi.), 487 ; pore (Scaph.), 



221 ; pores (Criu.), 377 



XENOCRINUS, 306 



Xflliiphnridcr, 6 



Xylopliaga, 21 



YOLDIA, 14 

 Ypsilotlitiria, 409 



ZEUGOSRANCHIA, 4 

 Zonites, S 



,, fi/lyens, apical system, 326 

 Zoroasteridce, 298 

 Zygoueury, 137 



THE END 



Printed l<y K. &; R. CI.AKK. LIMITKD, 



