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THE TYPES OF THE SPECIES OF ASCARIS 
DESCRIBED BY BAIRD. 
By H. A. BAYLIS, B.A. 1 
(With 3 Text-figures.) 
Eight forms, referred to the genus Ascaris, were described by 
Dr W. Baird between 1853 and 1868, all of which are represented by 
type-specimens in the British Museum collection. Stossich, in his 
monograph of the genus Ascaris (1896), mentions six of them, but all 
these are regarded by him as species inquirendae. Baird’s descriptions 
are in all cases brief, and confined almost entirely to external features, 
this rendering them inadequate for the requirements of present-day 
systematic workers. I have, therefore, thought it advisable to undertake 
a revision of the various types, with a view to deciding more definitely 
their systematic value, and, where possible, to re-describe those which 
appeared to me to represent valid species. 
Baird’s eight species are the following: 
1. Ascaris similis, 1853. Host, a Seal (Antarctic). 
2. ,, laevissima, 1853. Host unknown (India). 
3. ,, bifaria, 1853. Host unknown (Korea). 
4. „ obconica, 1860. Host Helicops [Uranop. s] angulatus (Brazil). 
5. ,, boddaertii, 1860. Host Herpetodryas boddaertii (West Indies). 
6. ,, salvini, 1860. Host Oreophasis derbianus (Guatemala). 
7. ,, unduloso-striata, 1862. Host Sarcorhamphus papa. 
8. „ bicolor, 1868. Host Odobenus rosmarus. 
Of these names, Ascaris laevissima and A. bifaria are omitted from 
his monograph by Stossich, who probably considered their validity too 
doubtful. 
I have already, in a previous paper 2 , attempted to deal with Ascaris 
similis and A. bicolor, upholding both these forms as valid species; 
1 Published by permission of the Trustees of the British Museum. 
2 Parasitology, Vol. vm, No. 3, p. 360. 
Parasitology vm 
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