NEMATODA 221 



power be increased to two hundred and fifty diameters linear." 

 As already stated in my introductory treatise, these observations 

 were made during the winter of 1853-54. In July, 1854, 

 M. Kobin made a similar statement after examining a fresh 

 Dracunculus which had been extracted from the leg of a man 

 by M. Malgaigne. Robin, not unsuitably, compared the worm 

 to a double tube, one tubular sheath, as it were, enclosing the 

 other. " The second tube," he distinctly affirms, " is the 

 oviduct, or, rather, that part which represents the uterus. The 

 young still remaining in the uterus were nearly all coiled, some- 

 times with the tail sallying outwards, at others rolled like the 

 rest of the body." I have thought it only due to Robin and 

 myself to show that from the first we were perfectly well 

 acquainted with the fact of the " great development of the 

 genital tube and of its close adherence to the parietes of the 

 body." To be sure, many discrepancies occurred in our 

 writings, and in those of Busk and Carter. It was Bastian' s 

 skill and good fortune to correct these errors. Thus, most of 

 us agreed in recognising a slightly trilobed or tripapillated 

 mouth ; but Carter failed to demonstrate the existence of these 

 tubercles, and spoke of the oral aperture as being simple and 

 " punctiform." The body throughout its three upper fourths 

 appeared to me to be cylindrical, but Robin found that it was 

 flattened. It is finely striated transversely, except at the part 

 where it contracts to form the slender, pointed tail. According 

 to Carter, Robin, and Davaine, the young attain a length of 

 about o-g of an inch, but Bastian gives it as about ^". In 

 thickness, Carter gives the approximative diameter as ^g", 

 Robin makes it ' to -n^/', whilst Bastian gives their breadth 

 at y^g"., and Davaine at 055". I estimated their greatest length 

 and breadth to be ?' by $" '. Robin and myself thought we 

 recognised a distinct, rounded, anal orifice ; and whilst Busk, 

 on the one hand, saw nothing which in the slightest degree 

 indicated the presence of an anal opening, Carter, on the other 

 hand, described the structure which we called the anus as a 

 gland, at the same time placing the alimentary outlet on one 

 side and a little above it. According to Bastian, " the intes- 

 tinal.tube is about ~" in length, and appears to consist of a 

 simple canal of varying calibre, pursuing a nearly straight 

 course, and terminating exactly at about the middle, in length, 

 of the worm. Like Robin, Bastian recognised oesophageal and 

 stomachal divisions, and in a few examples he observed the 



