226 J. MURRAY ON GASTROTRICHA. 



t 



Chaetonotus entzii (Dad.)? (11) (PL 19, fig. 26). 



A large animal, 250 to 300 jul and upwards in length. Head 

 obscurely 3-lobed, with two anterior processes, and two others at 

 posterior angles. Body long, nearly parallel-sided, covered with 

 apparently rhomboid scales, in diagonal rows, and fine short hairs, 

 gradually becoming longer posteriorly. Furca very long, nodose 

 (about twenty nodes in the length), widely divergent at base where 

 separated by small sulcus, less widely divergent above base. 



Habitat. Pond in the Praca Republica, Rio de Janeiro, Brazil ; 

 several specimens. 



About eight species of long-furcate nodose Gastrotrichs have 

 been described, which have all a suspiciously strong family likeness. 

 Some of these are certainly synonymous, their authors being 

 unaware of the existence of the other species. Daday, who is 

 responsible for the greater number of them, professes to draw 

 distinctions, but he is not very convincing, and moreover I have 

 found the animal here described to be extremely variable. 



Daday first described entzii as an Ichthydium, although it had 

 the characters of Chaetonotus. Later he described similar forms 

 as Lepidoderma, although some of them at any rate did not fit his 

 genus. Some he compared with entzii and with rhomboides Stokes, 

 noting that some had not the spines on the head, some had the 

 furca hairy, others smooth, etc. I cannot pretend to sort oat all 

 of these here, but content myself with pointing out the family 

 resemblance. 



Those I found in Rio had the hairs extremely variable, in some 

 very short, in others not visible at all. I could not doubt that 

 these were all one species, as I could see no other differences 

 whatever. The various species having long nodose furca will be 

 found noted in the list of all described species. 



Chaetonotus sp. (PI. 19, fig. 30). 



Large. Head short, 5-lobed, with cephalic shield, neck slightly 

 marked. Body clothed with simple hairs in about fifteen or 

 sixteen longitudinal rows, progressively longer posteriorly. Scales 

 like spear-heads, very like those of C. larus (fig. 9). The outline 

 of the body appears crenulate, with very prominent papillae in 

 the narrow part above the furca. About eight longer setae close 



