126 



THE PUE SEALS OF THE PRIBILOP ISLANDS. 



Fig. 28. 



0.48°"" from the tip, which is rounded and bears a small styliform process embedded 

 in the cuticle; vulva three- sevenths of the length from anterior extremity. The ova 

 (fig. 28) are spherical, 52 pi in diameter, with roundish elevations. 



Von Linstow does not believe that Dujardin's (1845) ^^Ascaris simplex Rud." (see 

 A. Bussumierii) is identical with the species he studied. 



Monticelli (1889, pp. 69, 70) records A, simplex from the stomach of 

 '^DelpMnus sp., of Porto La gunas (canali Patagonici)," taken by baptain 

 Chierchia in the voyage of the royal corvetta Vettor Pisani. His determi- 

 nation was made by comparing the specimens with the worms (N. 529, 829) 

 at the Vienna Museum determined by Diesing. It will thus be seen that 

 this record depends entirely upon a determination made before Krabbe definitely 

 defined Ascaris simplex, and on this account calls for confirmation. 



Braun (1891, p. 110) and Jagerskiold (1891) are not accessible to us at present. 



Jagerskiold (1894, pp. 474^476) examined specimens of A. simplex from Beluga 

 leueas [=I>elp}iinapterus leucas), which he had obtained from Levinsen ; he found the 

 bursa as well developed in these as in ^. angulivalvis Greplin 

 from Balaenoptera rostrata, and no longer doubts the identity of 

 the two forms. He describes the oesophagus (fig. 29) as com- 

 posed of two portions, an anterior longer portion, which increases 

 gradually in diameter, and a second shorter portion, which begins 

 with a swelling and then gradually decreases in size; no caeca 

 are present. The intestine' is provided with several rows of 

 groups of elongate cells, each group having a V shape, the apex 

 directed caudad. The excretory organ is about one-third as long 

 as the animal. The vulva was 36™" from the anterior end in a 

 specimen 72™™ long, and 70'"™ from the anterior end in one 150™™ 

 long, these measurements thus differing considerably from those 

 given by von Linstow (1888). The vagina is long and narrow, 

 the uterus bicorn. Jagerskiold inclines decidedly to the opinion 

 that A. Kukenthalii Oobb, from Beluga leucas (^Belphinapterus 

 leucas) is identical with A. simplex as defined by Krabbe, but, 

 being unable to examine specimens of Cobb's species, he reserves 

 positive judgment. 



Stossich (1896, p. 17) adds no new facts to our knowledge of 

 A. simplex. He considers A. delphini and A. Bussumierii, as well 

 as A. angulivalvis, as synonyms, but gives A. KUTcenthalii as a 

 distinct species. 



Regarding A. KiiJcenthalii see p. 144. 



Since finishing this manuscript we have received from Dr. von Marenzeller of 

 the Vienna Museum, a bottle of specimens with the label '■'■Ascaris simplex, Delphinus 

 pJiocaena." These worms we have redetermined as Ascaris typica (B. A. I., No. 2828). 

 The label does not show whether these parasites were determined by Diesing or not. 

 /?. Cuticular Lands do not exhibit the finer transverse striae, hut give a serrate appearance to the 



margin of the worm when viewed under a microscope; oesophageal and intestinal caeca 



absent. 



Eig. 29. 



