104 MR. H. CHARLTON BASTIAN’S MONOGRAPH 
near commencement. (Esophagus cylindrical, canal indicated by three bright lines. 
transverse muscular fibres not distinct. Intestine moderately well covered wid 
hepatic cells containing light-coloured fat-particles indistinctly aggregated. p, | 
about the middle of the body. Uterus bifid, segments symmetrical. Spicules — ; 
Lateral canals ——? Movements very sluggish. 
I. IGNAVUS, n.sp. (Pl. IX. figs. 34a, 34 b.) 
Female, length 4”, breadth 41". 
External Characters.—Body long and slender, tapering very gradually at both exi. 
mities, till, at the posterior, it terminates in a long filiform portion. Head bluntly 
rounded, provided with a circle of four very short setze. Integument having almos 
imperceptible longitudinal striæ, about 451.5" apart. 
Pharyngeal cavity long and narrow, having three small, rounded, valve-like plats 
near commencement. Œsophagus 4th of total length. Intestinal cells containing light. 
coloured, non-tessellated particles. Anus roo from posterior extremity. Vulva slightly 
anterior to the middle of body. 
Male, not seen. 
Hab. Stagnant water of Easthampstead Plain, amongst Diatomaceæ and decaying | 
Algæ ; also about the decaying submerged leaves of a species of Myriophyllum from the | 
lake, Sandhurst. 
5. DORYLAIMUS, Dujardin. 
Urolabes, Carter ; Anguillula, Grube. 
GEN. CHAR. Body sometimes blunt and rounded, sometimes filiform posteriorly. Caudal 
sucker absent. Integument having lon gitudinal markings, more or less visible, ani 
a series of minute pores on each side of body; setæ none; cephalic papillæ present 
or absent. Pharynx indistinct, but somewhat cup-shaped, having a long, homy 
and hollow exsertile spear projecting into and through it, which is renewed twice ot 
oftener during the period of growth. Œsophagus having the posterior half, or one 
third, of increased size; canal indicated by three bright lines; transverse musculi 
fibres not distinct. Infestine mostly well covered with hepatic cells containing fit 
Particles having a tessellated arrangement. Vulva about the middle of body. Uteris 
bifid, segments symmetrical, Spicules solitary, glaive-shaped ; males having some 
times a variable number of linear ventral suckers in mid line above anal cleft, ani 
also oblique markings of the integument. Lateral canals well developed and dis 
tinctly cellular. 
The Nematoid (D. stagnalis) found by 
certain fish, appears to me identical with t 
in mud from the bottom of freshwater 
marine representative of this genus, 
enough, the form which Carter has 
undoubtedly a member of the genu 
sucker amongst these, its habits 
Dujardin at Rennes, within the stomachs o 
hat form which I have met with so abundantly 
ponds. Dujardin also appears to have found 
though I have searched for such in vain. Curious 
taken as typical of his provisional genus Urolabes * 
8 Dorylaimus : and, from the absence of the cau" 
would probably not be of the nature indicated N 
