NEMATODA. 



291 



Attractonema gibbosum Lkt. in body-cavity of Cecidomyia pini, without 

 mouth and anus ; with alimentary canal reduced to a cell-cord ; with prolapsed 

 uterus and vagina, full of eggs, projecting from the body. Males and females 

 are found in the free state; they copulate; the female alone enters the host. 



Sphaerularia bombi* Leon. Duf., in the body-cavity of the humhie bees which 

 have survived the winter (Fig. 231) ; the life-history is similar to that of At. 

 gibbosum. The form in the body-cavity of the bee is the female, and consists 

 of a 15 mm. vermiform body carrying a small Nematode-like worm. The former 

 is the enormously grown protruded female generative apparatus, and the latter is 

 the body of the female worm, which alone enters the host. The larvae become 

 free in the bee, and leave it by the anus. 

 When free and 1 mm. long they become sexual 

 as males and females, and copulate. After 

 copulation the female enters the bee. 



Anguilhila Ehrbg. Small buccal cavity, 

 oesophagus with a posterior bulb and a 

 valvular apparatus. Male without bursa. 

 Usually two circular lateral organs. No 

 anal gland. A. aceti = glutinis 0. Fr. M., 

 the vinegar- and paste-worm 1-2 mm. long. 

 Chromadora Bast. ; Spilophora Bast. ; Odonto- 

 phora Bast. 



Fam. 7. Enoplidae.f Small, usually free- 

 living, marine forms, without the posterior 

 pharyngeal bulb, often with eyes and a buccal 

 armature, often with fine hairs and bristles 

 round the mouth. Dorylaimus Duj. ( Urolabes 

 Carter) ; D. palustris Cart., supposed by 

 Carter to be a non- parasitic stage in the 

 development of Filaria medinensis ; D. stag- 

 nalis found in mud everywhere in Europe. 

 Trilobus Bast.; Monhystera Bast.; Comesoma 

 Bast.; Enchdidium Ehrbg., a large eye on 

 the oesophagus, in the sea. Enoplus Duj., 

 marine ; Symplocostoma Bast. ; Oncholaimus 

 Duj.; Odontobius Roussel. 



The Chaetosomatidae and the Desmoscole- 

 cidae may be mentioned here. They are 

 minute non-parasitic, marine organisms, pre- 

 senting in the arrangement of their generative 

 organs resemblances to the Nematoda. Their 

 anatomy, however, is imperfectly known. 



FIG. 237. Desmoscolex minutus x 200. 

 a eye ; b ventral surface ; c long 

 dorsal bristles, which exist only 

 in the female ; d anus ; ventral 

 bristles (after Greef, from Perrier). 



* A. Schneider, Zool. Beitrage, Breslau, vol. i. R. Leuckart, "Zool. Anzeiger," 

 1885. Id., Neue Beitrage 2. Kennt. d. Nematoden, Leipzig, 1887. 



f Eberth, Unters. ub. Nematoden, Leipzig, 1863. Marion, "Rech. anat. et 

 physiol. sur les Nematoides non-parasites marins," Ann. Sc. Nat., XIII., 1870. 

 O. Biitsclili, "Ub. freileb. Nematoden, insb. d. Kieler Hafens," Abh. Senk. Nat. 

 Oesel. Frankfurt, 9, 1874. De Man, "Onderz. o. v. in der Aarde lev. Nematoden," 

 Tyds. d. Nederland. Tierkund. Vereenig, 1875. Id. " Contributions d la con- 

 naissance des Nematodcs du golfe de Naples," Leiden, 1876. 



