252 APPENDIX TO NEMATODA 



suggest, the worm does not appear from the figure to have been 

 a Nematode. It has rather the appearance of a Cestode, and 

 may have been a larval Tetrarhynchus. 



4. Discophorus Mehlis, in Creiilin, 1844. 

 Discophorus tenax Mehlis (in Creplin, 1844, Arch. f. Naturg., 

 X, 125) is a nomen nudum except for the mention of the host 

 {Raja davata). Writing again in 1846, Creplin (Arch. f. Naturg., 

 xii, 149) mentions D. tenax Mehlis as " nematoideum non 

 descriptum." 



5. Ditrachyceros Hermann, in Sultzer, 1801. 

 8yn. Ditrachyceras Sultzer; Ditrachycerosoma Brera, 1809; 

 Diceras Rudolphi, 1810, nee Lamarck, 1805; Dirhynchus 

 Rudolphi, 1810. 



The human " parasites " named Ditrachyceros by Hermann 

 (in Sultzer, 1801, Dissertation sur un ver intestinal, etc., 

 Strasbourg), and subsequently renamed Diceras rude by 

 Rudolphi (1810, Entozoorimi . . . Historia Naturalis, ii (2), 

 258), appear not to have been worms at all, but the seeds of a 

 plant, as was suggested by Bremser (1819, Uber lebende 

 warmer im lehenden Menschen, Wien, 261). 



6. Liorhynchus Rudolphi, 1801. 

 The type of this genus is indeterminable, and the name must 

 therefore lapse. It is a partial synonym of Spinitectus and 

 perhaps of other genera. 



7. Needhamia Carus, 1839. 



The objects found in the vas deferens of Sepia, and described 

 by Carus (1839, Nov. Act. Acad. Caes. Leop.-Car., Breslau and 

 Bonn, xix, i, 1) under the name of Needhamia expidsoria, 

 appear to have been simply the spermatophores of the Sepia 

 itself. 



8, Onchophora Kroyer, 1840. 



Syn. Oncophora Diesing, 1851. 



Body divided into two portions, of which the anterior is 

 very long and slender. Posterior portion thicker, shorter, 

 and bearing a hump * near the junction of the two portions. 

 Male unknown. Tail of female pointed. Viviparous. 



* This luimp, according to Rudolphi, may perhaps represent the 

 vulva. The (lescription was based on two females, of which the 

 anterior ends appear to have been missing. If the animal is a Nematode 

 (whicli seems uncertain), its shape suggests affinities with the Trichi- 

 nellidae, subfamily Triehurinae. The fact that it is stated to be 

 viviparous, however, is against this, and nothing whatever is known 

 of the internal anatomy. Diesing is referred to by Kroyer (1840), and 

 possibly is the author of the name Onchophora, in a personal communica- 

 tion. So far as Kroyer is concerned, the name is a nomen nvdum 

 except for the mention of the host. 



