ASCARIS HALirOKIS. 149 



Brandt (1846, i). 192) simply mentions the worms found by Riippell and Owen in 

 connection with the ascarides of Stellei's sea cow. 



Later Brandt (1849, p. 100) briefly refers to these parasites as follows: 



lu ventriculo ccternin nee nou glandulae cavo et dtiodeiio inveuit (Stelleius) lumhricos caiididoH 

 (Ascarides) uameiosos i longos. Simile (juid observaruut Riippelius (Museum Senkenb., I, p. 106) et 

 Oweuius (Zoolog. proceed., P. VI, p. 30) in Halicore. 



It is evidently this passage upon which the citation by some authors of the occur- 

 rence of ^4.. halicoris in Rhytina stelleri {^HyiJrodamalis f/igcis) has been based. It is 

 clear, however, that from the data at hand there is no justification for assuming that 

 the parasites from the two hosts are identical. 



Diesing (1851, p. 191) next cites this parasite as '■^Ascaris Dugonis Brandt" among 

 his species hKptirendae, referring to the articles by Riii)pell and Brandt (1846 and 

 1849). The name was not used by Brandt; it is to all purposes a nomen nudum, as the 

 description reads only "Longit. corj). 5." 



From a nomeuclatural standpoint the parasite was not described until 1869, when 

 Baird (1859, pp. 148, 149, \}l. LVi) figured it, and gave the following description: 



ASCARIS HALIOHORIS Owen. 



Capnt nudum, epidermide stricte adnata; os labiis rotundatis, porrectis; corpus, in utroque sexu, 

 estremitatibus magis attenuatis; extremitate caudali brevi, subulata. nuda. 



Long, feminae, 3:^ unc. ; maris, 2:!r uuc. 



The body is of a whitish color, thickest in the center, gradually tapering to ench extremity. The 

 body is strongly striated across; iii the female, apparently all its length; in the male, till nearly 

 about half an inch from its posterior extremity. This latter portion is smooth or slightly striated 

 lengthways. In the female the vagina is situated at about two-thirds of its length from the anterior 

 extremity. The spicula of the male appear very short. The intestine, as described by Professor 

 Ovren, has a caecum developed from it at the distance of about half an inch from the mouth, and is 

 continued upward, lying by its .side, and terminating in a blind extremity near the mouth. The 

 specimens, now in the British Museum, are shorter than those noticed by Rlipxiell. 



(The figures will explain this structure.) 



In the collection of the British Museum. 



Baird's (1860, pp. 329-331) second article is practically a reprint of his first dis- 

 cussion (1859). 



Diesing's (1860, p. 662) diagnosis is based upon Baird's (1859) description; Stos- 

 sich (1896, J). 68) gives a citation of this worm by Diesing (1861, Sitznngsber. k. Akad. 

 Wiss. Wien, XLYII, p. 277), but we have been unable to verify the reference. 



Von Linstow (1878, p. 59) gives both Halicore cetacea and Bhytina stelleri as har- 

 boring A. halicoris, but does not cite his authority for the latter host. 



Parona (1889) appears to be the next to discuss Asearis halicoris. He studied 

 specimens of ascarides collected by Vincezo Eagazzi in two Dugongs ("Halicore ceta- 

 cea") in Assab. After an historical review of the parasite he describes the anatomy 

 of Ragazzi's specimens, the description differing in some particulars from the diag- 

 nosis given by Baird. According to Parona the females measured 85 to 144'"'» in 

 length; with a maximum diameter of 3.5™"'; the males measured 85 to 115""" in 

 length. The bead is apparently without intermediate lips, and no mention is made 

 of labial dentition. A caecum is present running parallel to the oesophagus, as 

 described by Owen; in a female 135™™ long this caecum opens into the intestinal 

 tract 17"!"' from the mouth and measured 11""" in length. The vulva was about on 



