176 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



Fig. 44. Oesophagus of Aacaris typica from U.S.N.M., No. 5015, di vidod into an anterior straight poition 



and a posterior sigmoid portion. Intestinal and oesophageal caeca are absent. Zeiss 



4/a*io. Original. 

 Fig. 45. Lateral view of tail of male of Aacaris ti/pica from U.S.N.M., No. 5015, to show the structures 



described in the text. Zeiss 4/16, stage. Original. 

 Figs. 46-47. Ventral view of the tails of two male specimens of Ascaris simplex from U.S.N. M., No. 



5015, showing the unequal spicules and variations in the position of the caudal papillae. 



Zeiss 4/16, stage. Original, 

 Fig. 48. Eggs of Ascaris simplex from U.S.N.M., No. 5015, in various stages of segmentation. Zeiss 



4/4, stage. Original. 

 Fig. 49. A young specimen of Ascaris typica from U.S.N.M., No. 5015, partially surrounded by its larval 



cuticle. Zeiss 4/a* 1(1. ' 

 Fig. 50. Anterior extremity of a young specimen of Ascaris typica which has cast part of its larval 



cuticle. Zeiss 4/8-, stage. Original. 

 Fig. 51. Caudal extremity of a young specimen of Ascaris typica before the larval cuticle has been 



cast. Zeiss 4/8, stage. Original. 

 Figs. 52-56 are given in text. 

 Fig. 57. Dorsal lip of Ascaris patagonica, showing the double dentigerous ridge and other structures 



given in the diagnosis. After von Linstow, 1880, pi. Ill, fig. 1. 

 Fig. 5S. Maie of Ascaris Eiikentlialii. Natural size. After Cobb, 1888, pi. iii, fig. 1. 

 Fig. 59. Male of Ascaris KUkenfhalii, opened on the left side to show the anatomy : 6., bulbus of the 



oesophagus; de., "end portion of the intestine" (or ductus ejaculatorius?); ed., rectum; 



CO., excretory organ; ft., testicle; Icmd., smaller portion of the intestine; I., glandular 



organ; m., mouth; mh., bursal muscles; md., intestine; msp., muscles of a spicule; 



oe., oesophagus; 82.,vas deferens; sp., spicules; 88.,vesicala8eminalis("Sanienschlauch"). 



After Cobb, 1888, pi. in, fig. 7. 

 Fig. 60. Tail of male of Ascaris Eiikenihalii, opened ventrally to show the anatomy: a., anus; 



de., ductus ejaculatorius; dim., dorsal longitudinal muscle; ed., rectum; h., testicle; 



mb., bursal muscle; «/., lateral line; sfi., broadened portion of lateral line; 82., yas 



deferens; sp., spicules; ss., vesioula seminalis ("Samenschlauch"). x 2. After Cobb, 



1888, pi. in, fig. 5. 

 IFig. 61. Ventral view of tail of male of .48cans KUlcenthaUi, showing" the cloaca and caudal papillae as 



as seen by Cobb. After Cobb, 1888, pi. in, fig. 3. 

 Fig. 62. Apex view of head, showing the position of the lips : pe, excretory pore, x 50. After Cobb, 



1888, pi. Ill, fig. 11. 

 Fig. 63. Female specimen of .4scan8 Eiikenthalii. Natural size. After Cobb, 1888, pi. in, fig. 2. 

 Fig. 64. Anterior extremity of Ascaris KUkentliaUi, opened ventrally to show the anatomy : ag., termi- 

 nal duct of excretory organ; eo., excretory organ; esf., constriction of lateral field; 



geo., duct of excretory organ; m., mouth; md., intestine; nr., neural ring; om., muscle; 



rn., dorsal nerve; s/., lateral line, x 2. After Cobb, 1888, pi. in, fig. 4. 

 Pig. 65. Ascaris similis, natural size, after Baird, 1853, pi. i, fig. la. Baird states that this is a male, 



but it is more probably a female. 

 Fig. 66. Head of male, magnified, showing three lips; intermediate lips are absent. After Baird, 



1853, pi. I, fig. Id. After Baird, 1853, pi, i, fig. 16. 

 Fig. 67. Ascaris similia, natural size, after Baird, 1853, pi. i, fig. Ic. Baird states that this is a female, 



but it is more probably a male. 

 Fig. 68. Head of female, magnified, after Baird, 1853, pi. i, fig. Id. 

 Fig. 69. Tail of female, magnified, after Baird, 1853, pi. i, fig. le. 

 Fig. 70. Ascaris halicoris, after Baird, 1859, pi. lvi, fig. 2. 

 Fig. 71. Head of Ascaris halicoris, showing the three lips; intermediate lips are absent. After Baird, 



1859, pi. LVI, fig. 2a. 

 Fig. 72. Tail of Ascaris halicoris, after Baird, 1859, pi. lvi, fig. 26. 

 Fig. 73. Anterior portion of Ascaris halicoris, dissected to show the oesophagus, intestine, intestinal 



caecum, and a portion of the genital organs. After Baird, 1859, pi. lvi, fig. 2c. 

 Fig. 74. Transverse section of head of Ascaris halicoris, showing the relative position of the three lips 



and the absence of intermediate lips. After Parona, 1889, pi. xiii, fig. 3. 



