486 On the Nematocysts of Solids. [Nov. 3, 



16. Herdman and Clubb, " Third Report on Nudibranchiata of L.M.B.C. District," 



' Trans. Liverpool. Biol. Soc.,' vol. 4, 1890, pp. 150 163. 



17. Iwanzoff, " Ueber den Bau, die Wirkungsweise und die Entwickelung der 



Nesselkapseln der Coelenteraten," * Bull. Soc. Imp. Mosc.,' 1896. 



18. Krembzow, E., " Ueber Bau und Entwickelung der Riickenanhiinge bei 



Aeolidiens," ' Arch, fur Micr. Anat.,' vol. 59, 1902. 



19. von Lendenfeld, " Nesselzellen der Cnidaria," ' Biol. Centr.,' vol. 17, 1897. 



20. Simroth, " Ueber der Verdauungscanal bei Weichthiere," ' Sitzungsb. Nat. Ges. 



Leipzig,' 26/27 Jarhg. 



21. Trinchese, S., 'Aeolididee e Famiglie affine nel Porto di Geneva/ Part I, 



Bologna, 1877-79; Pt. II, Roma, 1881. 



22. Vayssiere, " Recherches Zoologiques et Anatomiques sur les Mollusques Opistho- 



branches du Golfe de Marseille, II Pt. Nudibranches," 'Ann. Mus. 

 Hist. Nat. Mars., Zool.,' vol. 3, p. 4, 1888. 



EXPLANATION OP FIGURES. 



Fig, 1. Small Pip-shaped Nematocysts of Tentacles of Eudendrium from Cuidosac 



of Rizzolia peregrina. x 560. 



2. Nematocysts of Pennaria Cavolinii. x 560. 

 3. Nematocysts of Tubularia. x 560. 

 4. Large Bean-shaped Nematocysts from Body of Polyp of Eudendrium. 



x560. 



5. Nematocysts from Cnidosacs of Facelina pvnctata, specimen B. x 900. 

 6. Large oblong Nematocysts from Flabellina ajfini*. x 560. 



a. Tip of Basal portion of Thread, x 900. 

 7. Nematocysts of Aiptasia variabilis. x 560. 



8. Actinian Nematocysts from Cnidosacs of Spurilla neapolitana. x 560. 

 9. Nematocysts from young Specimen of Spurilla neapolitana. x 560. 



a. Ditto. x900. 

 10. Nematocysts from Cnidosac of Aeolidiella Alderi. x 560. 



a. From Acontia of Sagartia. b. From Tentacles of same. 



,, 11. Oblique Section through young Cnidosac of Spur ilia neapolitana. Stained 

 with Ehrlich-Biondi. x 1360. 



Smb., embrionio zone at base of cnidosac; Cn. bl., cnidoblast ; 

 Nem., nematocyet; Ct., membranous cyst; Int., interstitial 

 cells, nuclei stained greenish; Int.', degenerate interstitial 

 cell, nuclei stained red. 

 12. Small Portion of another Section of the same Cnidosac. 



Cn. bl., cnidoblasts ; -V., nucleus of same, stained reddish ; 

 JIT, nucleus of interstitial cell, stained green; I. m., longitudinal 

 muscles ; c. m., circular muscles ; Nem., nematocyst. 



13. Transverse Section through middle of a Cnidosac of E. peregrina, fed on 

 Pennaria Cavolinii for one month. Some of the cnidoblasts are 

 already surrounded by membranous cysts, while others are still ingest, 

 ing nematocysts. Stained with thionin. x 800. 



Nem. 1, large nematocyst of Pen. Cavolinii just being ingested. 

 Nem. 2, small stained reddish-violet. 



Nem. 9, pale blue. 



Nem. 4, Eudendrium nematocyst. 



