98 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



muscles. Female pore to left of male pore. Ovary slightly lobed, to 

 right of mid-line, anterior to testes. Shell gland posterior to ovary, 

 median, well developed, without outer membrane. Seminal recep- 

 tacle and Laurer's canal apparently absent. Vitellaria in large irregu- 

 lar follicles extending lateral to ceca from anterior level of testes 

 to posterior level of seminal vesicle. Uterus in transverse coils, inter- 

 cecal, from ovary to female pore. Eggs 59 to 63 ^i by 25 to 36 [x, with 

 many long filaments, about 133 /x long, at each pole. Excretory vesi- 

 cle Y-shaped, with numerous short branches on limbs. 



The generic name is from the Greek myo (muscle) and saccus 

 (sac), descriptive of the very muscular cirrus sac. The species name 

 is for the host. 



Comparisons. Myosaccus differs from Iguanacola in its body 

 form, cirrus sac, and excretory system. Epibathra Looss, 1902 differs 

 in that the cirrus is not divided, the prostate is not surrounded by 

 muscles, and the collar and excretory system are very different. 

 Adenogaster Looss, 1901 has a divided cirrus, and the position of 

 the ovary, testes, and shell gland are almost the same as in Myo- 

 saccus. Adenogaster, however, differs in its long simple prostate, the 

 lack of a muscular sheath about the prostate, the absence of pos- 

 terior papillae and the presence of four rows of ventral glands. The 

 cirrus of Diaschistorchis Johnston, 1913 resembles this genus in its 

 musculature, but almost all other characters are different. Pyeloso- 

 mum Looss, 1899 has a horizontal cirrus sac but it is undivided 

 and thin-walled and no papillae occur at the posterior end of the 

 body. 



Subfamily: Teloporiinae Stunkard, 1934 



Cetiosaccus galapagensis, new genus, new species 

 (Plate 12, figs. 9-11) 



Host: Amblyrhynchus cristatus 

 Location: Intestine 

 Locality: Albemarle Island 



The body is very long and narrow, measuring 7 to 13 mm. in 

 length by 1 to 1.3 mm. in greatest width. The width is greatest in 

 the anterior fourth of the body. The body is without spines or pos- 

 terior papillae. The excretory pore is located on a muscular protu- 



