Eycleshymer-Davis, Epiphysis and Paraphysis in Amia. 69 



ABBREVIATIONS. 



c. — Cartilage. /. — Pigment. 



ei. — Primary epiphysial vesicle. pc. — Posterior commissure. 



€2. — Secondary epiphysial vesicle. r. — Roof of thalamencephalon. 



ej>. — Epithelium. sc. — Superior commissure. 



ft. — Fibre tract. th. — Thalamocoele. 

 nf. — Nerve fibre. 



EXPLANATION OF FIGURES. 

 PLATE VII. 



Fig. I. Sagittal section through the epiphysial fold of an embryo whicli 

 extends over about two-thirds of the meridional circumference of the egg. 

 X 160. 



Fig. 2. Transverse section of the same stage x 160. 



Fig. 3- Sagittal section through the epiphysial or primary vesicle at the 

 stage when the tail of the embryo is first free from the yolk, x i6o.j 



Fig, 4. Transverse section of same stage along the line 4-4 of Fig. 3. 

 X 160. 



Fig. J". Reconstruction of primary vesicle of larva 6-7 days old. (4-5 mm). 

 X50. 



Fig. 6. Sagittal section of the same stage along the line 6-6 of Fig. 5. 

 X 160. 



Fig. 7. Transverse section of same stage along the line 7-7 of Fig. 6. 

 X 160. 



Fig. 8. Sagittal section of primary vesicle of larva 8-9 days old (5-6 

 mm). X 160. 



Fig. p. Reconstruction of primary and secondary vesicles of larva 9 days 

 old (6-7 mm). X 50. 



Fig. 10. Sagittal section of same stage taken along the line 10-10 of Fig. 

 9. X 160. 



Fig, II. Transverse section of same stage along the line ii-ii of Fig. 10. 

 X 160. 



Fig. 12. Transverse section of same stage through the secondary vesicle 

 along the line 12-12 of Fig. 10. x 160. 



Fig. jj. Reconstruction of primary and secondary vesicles of larva 10 

 days old (7-8 mm.) showing shifting of secondary vesicle to the left, x 50. 



Fig. 14. Sagittal section of the roof of the thalamencephalon through the 

 epiphysial region along the line 14-14 of Fig. 13, x 15, 



Fig. ij. Sagittal section of the epiphysial region of Fig. 14. x 160. 



Fig. 16. Transverse section of same stage along the line 16-16 of Fig. 13. 

 X 160. 



