•65 



ANTICOMA : 

 A GENUS OF FREE-LIVING MARINE NEMATODES. 



By N". a. Cobb. 



The first carefully described Anticoma was taken by Eberth 

 from the Mediterranean Sea, and it figured in th-at autlior's 

 " Untersuchungen iiber Nematodeii " as Odontohius acinninatus. 

 Seemingly by a misprint, the neck was stated to be one-third as long 

 as the body. This led Bastian, who was the next naturalist to 

 discover one of these worms, and the first to realise their proper 

 systematic position, to describe as a species distinct from Eberth's, 

 Anticoma limalis. Nevertheless Bastian's limalis was doubtless 

 identical with Eberth's Odontohiits acuminatus, as Biitschli has 

 already suggested. Bastian saw the necessity of creating a new 

 genus for his species, and therefore originated the n?i\ne Anticoma. 

 Living with his Anticoma limalis Bastian found another worm, to 

 which he gave the name Anticoma pellucida. This latter did not 

 differ in proportions from limalis, nor much in size. Bastian failed 

 however to discover in it the ventral gland, and this, together with 

 the fact that he failed also to see the pectoral hairs in limalis, Avas 

 doubtless his reason for describing it as a separate species. I think 

 there can be no doubt that it was specifically identical with limalis. 

 Biitschli, who afterwards found limalis at Kiel, pointed out the 

 position and number of the pectoral hairs, and his figure shows 

 these hairs exactly as given in Bastian's figure for pellucida. 



The next naturalist to find an Anticoma was Villot, but neither 

 Villot's descriptions nor his figures are adequate for the detevmina- 

 tion of the species which he observed. He saw Bastian's limalis, 

 and mentions under the head of Anticoma two other species, one 

 of vvhich is certainly not a member of that genus, and the other 

 possibly not. 



