122 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



may show that A. KillcenthaUi Cobb (see p. 144) is synonymous with the form now 

 under discussion. In detail the history of A, simplex is as follows : 



Historical Review. — Eudolphi's (1809, p. 170) original diagnosis reads as 

 follows : 



35. Ascaris simplex R. 



Ascaris : Capite tenuiore caudaque ieretibus ohtuais. 



H.ib. ; In DelpMni Phocaenae ventriculo primo ab am. Albers magna copia reperta, et mecum 

 communicata. 



Descr. : Vermes pollicem vel sesquipollicem longi, crassiusculi, albidi, apiraliter convoluti. 



Caput obtusum, trivalve, valvulis exiguis. Corpus undique teres, utrinque, antrorsnm tameu 

 magis attenuatum. Cauda obtusa. Membrana linearis nullibi oonspicua. 



Obs. : Inter speoimiua plurima vix uniim alterumve possideo, cujus cutis vel in antica vel in postica 

 parte in processum pellucidum et vacuum protracta uon sit, ut Asoaride obiter spectata mox. caput 

 mox Cauda vacua appareat. Nil nisi empbysema post mortem obortum, cutem laxiorem tamen indicans, 

 alias enim haec in arenas potius abiisset. 



Later Rudolphi (1819, p. 49) adds : 



Abo. capite undo, corpore retrosnm orassiore, cauda obtusa. * * * An hue n. 82? 



N. 82, to which he refers, is Ascaris delphini, cited by Eudolphi (1819, pp. 54, 296) 

 as having been collected by Lebeck in BelpMnus gangeticus (= Platanista gangetica). 

 There is, however, nothing in Lebeck's citation of the worm which warrants the 

 assumption that his form was Ascaris simplex, and although nearly all authors consider 

 it a synonym of that species,. and on this ground give A. simplex sls one of the parasites 

 of Flatanista gangetica, it seems to iis much more logical to dispose of the doubtful 

 species A. delphini by making it a doubtful synonym of Ascaris lobulata, which is 

 described from the same host species (P. gangetica), or by ignoring it entirely. (See 

 p. 162.) 



Regarding the worms which Dujardin (1845, pp. 220, 221) determined as Ascaris 

 simplex Rudolphi some difference of opinion exists among authors. Diesing (1851, p. 

 155) and Stossich (1896, p. 17) accept the determination as correct, while van Beneden 

 (1870, p. 362) considers that these parasites represent a distinct species A. Bussumierii; 

 von Linstow (1888, p. 3) even doubts whether the Dujardiri's worms belong to the 

 genus Ascaris. The host was a dolphin, taken near the Maldives in 18.'50. (See 

 p. 161.) 



Creplin (1851, pp. 158, 160) described under the name Ascaris angulivalvis- three 

 specimens of nematodes taken from Balaena rostrata (=Bala^noptera rostrata); the 

 worms were given to him by Oskar Schmidt, who received them in 1850 from Mr, Koren, 

 of Bergen. One' of the specimens was deposited in the Zoological Museum in Greifs- 

 wald. More exact data concerning the origin of specimens were not published. Creplin 

 was unable to utilize Rudolphi's diagnosis ot A. simplex in trying to determine his own 

 specimens, since the description was so poor, but he considered his parasite closely 

 related to, yet perfectly distinct from, the worms which Dujardin determined as 

 A. simplex. Creplin's description reads as follows: 



Die drei oben erwahnten Speeimina bestauden in einem — dem Anschein naoh — erwachsenen Paare 

 und einem jiingeren Weibohen. Sie waren sammtlich sohmutzig grau von Farbe. Das Miinnohen des 

 Paares war ungefiihr 2J" lang und in der Mitte li" ' dick, das "Weibohen desselben etwa 3i" lang imd 

 in der Mitte 1^" ' dick. Das jiiugere Weibcben hatte eine Liinge von 2" nnd eine mittlcre Dicke von 

 c. i'". Beide Gesohlecbter waren nacb voni ein wenig melir, als nacb hinten, verschmiichtigt ; von 

 Seitenraembranen fehlte bier, wie bei Rudolphi's und Dujardin's Species, jede Spur. 



