194 OHAS. B. WILSON. 



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Micr. Sci./ vol. xviii, 1878. 



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'Zool. Bull.,' vol. ii, No. 1, 1898. 



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some Polycliaitous Annelids," ' Stud. Biol. Lab. Johns Hopkins Univ.,' 

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EXPLANATION OF PLATES 9—11, 



Illustrating Mr. Chas. B. Wilson's paper on " The Habits 

 and Early Development of Cerebratulus lacteus 

 (Verrill)." 



Key to Letters, 



am. A|)ical muscle, ant. Anterior invagination, bv. Blood-vessel, c. 

 Intestinal caeca, cc. Cilia cells, cm. Circular muscles, com. Circumoral 

 muscle, ct. Connective tissue, dvm. Dorso-ventral muscles, ec. Ectoderm. 

 en. Entoderm, gc. Gelatine cell. glc. Gland-cell, gr. Groove for food. im. 

 Interparietal muscle, lam. Lappet muscles. Im. Longitudinal muscles. 

 lorn. Locomotor muscles, o. Ovary, ce. (Esophagus, pm. Post-oesophageal 

 muscle, s. Stomach, sc. Sperm mother- cell. /, Testis, wc. Wall-cell, 

 yc. Yolk-cell. 



PLATE 9. 



Fig. 1, — Ceiebratulus swallowing a Nereis five minutes after dismembering 

 the posterior half of its body. Photograph from preserved specimen, one 

 eighth life size. 



Fig, 2, — Cerebratulus with regenerating papilla. Photograph from life, 

 one eighth life size. 



