368 Part III. — Eighteenth Annual Re-port 



45. Raffaele, F. — " Le Uova Gall, e le Larve d. Teleostei nel Golfo di Napoli," 



Mitt. a. d. Zool.-St.at. zu-Neapel, VIII. , 1888. 



46. Ryder, J. A. — " On the Origin of Heterocercy and the Evolution of the Fins 



and Fin-rays of Fishes," U.S. Comm. Fish and Fisheries, 1884. 



47. Sauvage, E. — " Memoire sur la Faune Ichthyologique de la Periode Tertiaire," 



Comptes Rendus, Paris, 1872. 



48. Sagemehl, M. — " Beitrage zur vergleichenden Anatomie der Fische," I. -II. 



Morph. Jahrbuch, B. IX., 1884. 



49. Sagemehl, M. — "Beitrage zur vergleichenden Anatomie der Fische," III. > 



ibid., B. X., 1885. 



50. Smitt, F. A. — " Scandinavian Fishes," 1892. 



51. Stannius, H. — "Anatomie der Wirbelthiere," Berlin, 1854. 



52. Steenstrup, J. — "Fortsatte Bidrag— Oiestillingen hos Flyndrene," Copen- 



hagen, 1878. 



53. Thompson, D. W. — "On a Supposed Resemblance between the Marine 



Faunas of the Arctic and Antarctic Regions," Proc. Roy. Soc. E., 1898. 



54. Traquair, R. H. — "On the Asymmetry of the Pleuronectida?," Tr. Linn. Soc, 



1865. 



55. Wiedersheim, R. — " Grundriss der vergleichenden Anatomie der Wirbel- 



thiere," Jena, 1898. 



56. Williamson, H. C. — "Anatomy of the Pectoral Arch of the Grey Gurnard 



(T. gumardus)," S.F.B. Rep., XII. , 1893. 



DESCRIPTION OF PLATES (XI. -XII.) 



Fig. 1. Pleuronectes platessa ; viewed from in front, to show relative positions 



of dorsal fin (D. ) and nasal organs (l.n.o. and r.n.o. ). 

 Fig. 2. Hippoglossus vulgaris ; do. 

 Fig. 3. Rhombus maximus ; do. 

 Fig. 4. Solea hleinii ; do. 



Fig. 5. Hippoglossus vulgaris ; to show olfactory organ (o.o. ) of right (or eyed) 

 side and nasal sacs (r.n.s. and l.n.s.). The lamina? of the sensory 

 epithelium are arranged longitudinally to the main axis of the body. 



Fig. 6. Rhombus maximus ; olfactory organ of left (or eyed) side. The lamina? 



are arranged transversely to the main axis about a longitudinal rachis. 



Fig. 7. Solea lascaris ; olfactory organ of left (or blind) side. The olfactory 

 lamina? are arranged longitudinally, the median rachis transversely, 

 to the main axis. 



Fig. 8. Rhombus maximus ; abdominal and five of the caudal vertebrae, showing 

 the unclosed nature of the ribs (p.r.) and parapophyses (p.p.), the 

 transverse processes of the caudal vertebra? (t.p.) continuing into the 

 " pleura-pophyses " (p.p.) of the abdominal vertebra?, and the first 

 interha?mal spine curved forward at its extremity and continued by 

 two small portions of cartilage, so that the abdominal cavity is almost 

 completely enclosed. 



Fig. 9. Solea vulgaris ; abdominal and four of the caudal vertebra?. The haemal 

 arches are closed (h.p. ), the transverse processes of the caudal vertebra? 

 are continued by true transverse processes on the abdominal vertebra?. 

 There is no single first interha?mal spine, but a group of four. These, 

 and not the " ha?mapophyses," mark the commencement of the caudal 

 vertebra?. 



Fig. 10. Solea vidgaris ; third last abdominal vertebra. The haemal arches are 



completely fused to form ha?mapophyses. 

 Fig. 11. Rhombus maximus ; third-last abdominal vertebra. The ha?mal arches 



and ribs are free. 



Fig. 12. Rhomboidichthys mancus ; third-last abdominal vertebra. Haemal arches 



as in S. vulgaris. 

 Fig. 13. Citharus linguatula ; termination of vertebral column. 

 Fig. 14. Solea vulgaris ; do. 

 Fig. 15. Ibid. ; from post-larval specimen ; do. 

 Fig. 16. Rhombus maximus ; do. 

 Fig. 17. Ammopleurops lacteus ; do. 



