PLATE LXXIII. 



Figs. 45-48. Ualdxuiiruii man-ocMr. 



Fig. 45. Transverse vertical section of the ylamlular jdiosphoiescent organ below the gill-cover. x 15. 

 n. Granular substance ; h, vertical threads ; e, stnicturcless reflecting cuticular membrane ; d, pigment- 

 layer. 



Fig. 46. Transverse vei-tical section of the same organ. x 250. 



u, Granular substance ; b, vertical threads, consisting of blood-vessels, nerves, and a cartilaginous 

 supnort ; c, structureless reflecting cuticular basal membrane : d, pigment-layer ; e, outer pavement 

 epitneliuni. 



Fig. 47. Tripolar cell from the granular substance, x 600. 



Fig. 48. Bipolar ceil from the saue. x 600. 



Figs. 49-53. XetiotlerniichtJiiji' iwdidosun. 



Fig. 49. TrausveiBe vertical section of the ducts of the sHine-glands in the .sides of the body. x 100. 

 «, Outer pavement epithelium with .scattercil pigment ; b, proximal iinl of elll-rent duct ; i/, thick pig- 

 ment-layer of the dermis ; rf, transparent til>rou.s tissue. 



Fig. 50. Axiid .section of a jirojecting ocellar phosphorescent organ, from the side of the body. x 100. 

 ii. Thick pigment-layer of the deiniis ; /', outer pavement epithelium, with scattered pigment; c, thick 

 pignient-Iayer covering the upper ino.xini.ii portion of the organ ; d, internal crest dividing the 

 organ into a proximal and a distal portion ; > , limit of the pigment cover i /, nerx'e passing into the 

 organ : </, thick pigment-layer on the proximal side ; A, [jroximal granular portion, with large nuclei : 

 (', typical phosphorescent clavate cells ; k; pigment patches ; /, transparent epithelium. 



Fig. 51. BipoliU' cell from the distal portion of the same organ. x 800. 



Fig. 52. Typical phosphorescent clavate cells, from the same. x 800. 

 It, Light-refracting vesicle ; b, nucleus ; c, peduncle. 



Fig. 53. A similar clavate cell with abnormal refractive vesicle, froju the same. x 800. 



a, Two light-refracting vesicles ; b, nucleus ; i-, iiedimde. 



Figs. 54-64. tialosaurus macrochir. 



Pig. 54. Surface view of the retiecting membrane, clothing the spaces between the modified scales of the 

 lateral line. x 1 400. 



Fig. 55. Transverse section of the large lateral slime-canal. x 150. 



a, Phosphorescent tissue overlying the slime-canal ; b, gland-tubes ; i-, short cylindric;d lungitudiually 

 situated cells, with well-deliMe<I rcll-wall, occujiying the lower portions of the slime-canal ; d, irre- 

 gular cells surrounding the lumen ul the slime-canal ; <■, lumen of the slime-canal ; f, muscular fibres. 



Fig. 56. Tripolai' cell, from the slime-canal; adjacent to the lumen, x 400. 



Fig. 57. Bipolar cell, froui the same situation. x 400. 



Fig. 58. Group of cells, from the slime-canal ; adjacent to the outer wall, m transverse section. x 500. 



Fig. 59. Coiled gland-tubes, from the vicinity of the slime-canal, x 300. 



Fig. 60. Longitudinal section of the tissue occupying the spaces below the large modified scales of the 

 lateral line. x 500. 

 ft, Lenticular yellow bodies ; b, intervening fibrous tissue. 



Fig. 61. Longitudinal section through the slime-canal, showing the plio.sphorescent organs, in the modi- 

 fied lateral line. x 150. 



«, Mu.srular fibres ; b, inner poi tion of the tissue filling the .slime-canal ; c. lumen of the slime-canal ; d, 

 extensions of tlie lumen lielow the inner margin of each scale ; <. extension of the roof of the slime- 

 canal along the outer side of the proximal ]iortion of each mollified scale ; /, tissue covering the 

 slime-canal ; ij, tissue between the modified scales of the lateial line ; h, roof of the slime-eanal ; 

 i, modified scales of the lateral line ; /■. jiosterior margin of the scale ; /, pigmenteil membrane 

 covering the outer surface of the modified scales ; ■/«, pigmented membrane covering the inner 

 surface of the modified scales ; n, reflecting membrane on the inner side of the modified scales ; 

 y, reflecting membrane on the outer side of the modified scales ; /), phosphorescent organ on the 

 outer side of the scale ; q, transverse ridge of the scale ; /■, inner membrane ; v. outer membrane ; 

 t, canal passing through the scale and leading to the phosphorescent organ. 



Fig. 62. Longitudinal section of a portion of the lateral line, near the proximal end of one of the 



modified scales, x 400. 



'/, Phosphorescent tissue overlying the slime-caual ; b, reflecting membrane \ e, pigmented membrane 



below the scale ; d, scale ; c, pigmented membrane ; /", reflecting membrane above the scale ; 



(J, extension of the roof of the slime-canal along the outer side of the proximal portion of the scale ; 



A, fibrous tissue ; ;', lenticular yellow bodies of the tissue between the scales. 



Fig. 63. Longitudinal section of the slime-canal, showing the phosphorescent organs in the modified 

 lateral line. x 60. 

 '(, Lumen of the slime-canal ; /', tissue of the slime-caual ; c, tissue between adjacent modified scales ; 

 d, scales and their membranes (compare fig. 62). 



Fig. 64. Transverse section of a phosphorescent organ attached to the outer side of the scale, x 400. 

 a, Blood-vessob ; b, ganglion cells ; c, phos|)1ioresceut spindle cells : d, gianular superficial layer. 



