DEVELOPMENT AND LIFE-HISTOKIES OP TELEOSTEAN PISHES. 943 



Pig. 8. Salmon about a fortnight old. 



Pig. 9. Another example, slightly older, presenting differences in the outline of the yolk-sac and 



oil-globule. 

 Pig. 10. Salmon, 1 month old, viewed from the dorsum. 

 Fig. 11. Salmon, 5 weeks old, in profile. 

 Pig. 12. Embryo of the gurnard (Triglot, gurnardus), showing early optic vesicles and myotomes, 



also compound vesicles anterior and posterior to Kupffer's vesicle, . . x 50 



Plate XXIII. 



Fig. 1 . Transverse vertical section (slightly oblique) of the head of the larval Anarrhichas, January 

 23, 1886, through the optic lobes, optic thalami, and anterior lobes : ovf, valve-like 

 flap of the optic lobes, . . . . . . . . x 40 



Fig. 2. Horizontal section through the anterior region of the same species, February 20, 1 886, show- 

 ing the fourth ventricle, parachordals abutting on the oral end of notochord, pronephros, 

 and other parts, . . . . . . . . x 40 



Fig. 3. Transverse vertical section through the fore-brain and the commencing optic lobes, the 

 thalamencephalic chamber opening into the ventricle of the fore-brain beneath : flm, 

 flap of mucous membrane at the side of the mouth, March 16, 1886, . . x 40 



Fig. 3a.Section somewhat behind the foregoing, showing the pineal gland and other parts, March 



16, 1886, . . . . . . . . . x 40 



Fig. 4. Transverse vertical section through the infundibulum and lobi inferiores : ms, muscles ; ct, 



connective tissue, June 20, 1886, . . . . . . x 97 



Fig. 5. Transverse vertical section through the pineal region, showing the posterior commissural 



bands of fibres, June 20, 1886, . . . . . . x 97 



Fig. 6. Transverse vertical (slightly oblique) section through the optic lobes and infundibulum of 



the same form, .......... Magnified 



Pig. 7. Transverse vertical section of tip of snout and through the nasal pits of the ling. The 



anterior epiblast is in contact with the hypoblast, . . . . x 135 



Fig. 8. Caudal extremity and Kupffer's vesicle of the embryo of Gadus ceglefinus, . . x 45 



Fig. 9. Embryo of Gadus a'glefinus, showing neurenteric canal, 9th day after fertilisation, . . x 45 



Fig. 10. Larva of Solea vulgaris, posterior aspect of the globular yolk, with large vesicles in proximity 



to the mass of oil-globules beneath the trunk, . . . . . x 40 



Plate XXIV. 



Fig. 1. Longitudinal vertical section of the head of the larval Anarrhichas nearly in the median 



line, January 23, 1886, . . . . . . . x 50 



Fig. 2. Similar section on one side of the median line, . . . . . x 40 



Fig. 3. Transverse vertical section of the head of the same form through the tori semicirculares and 



commencement of the notochord, January 16, 1886, . . . . x 52 



Pig. 4. Horizontal section through the anterior end of the fore-brain, with the olfactory bulbs 



(oil) and nerves (I.), June 20, 1886, . . . . . . x 52 



Pig. 5. Transverse vertical section of the brain of Anarrhichas, just behind the anterior commissure, 



traces of which are still present in the section, January 16, 1886, . . x 52 



Fig. 6. Similar section behind the former, showing the roof of the fore-brain, and the inferior 



fibres, fa, behind the optic tract, January 16, 1886, . . . . x 52 



Fig. 7. Circulation of the yolk-sac in the advanced larval Anarrhichas from the right side, March 



31, 1886, .......... Magnified 



Plate XXV. 



Pig. 1. Horizontal section through the heart and hyoid region of the larval Anarrhichas, March 29, 



1886 : chy, ceratohyal ; hhy, hypohyal, . . . . . x 60 



