F. H. Stewart 
163 
Key to the group of the slender-bodied Aphelenohi. 
Aphelenchi of slender-body form, a 1 , 45 and over. 
(1) Excretory pore behind the nerve ring. Parasitic. L. 0*85-1 mm. 
A. phyllophagus n.sp. 
(2) Excretory pore at the level of the nerve ring. 
(a) Intra-uterine egg rounded oval. Free living. L. 1 mm. A. helo- 
philus De Man, 1886. 
(b) Intra-uterine egg elongated cylindrical. Parasitic. 
(i) Anterior lip of anus prominent. Causes hypertrophy of 
tissues of host. L. 0*07-0*08 mm. A. fragariae R.B., 1891. 
(ii) Anterior lip of anus not prominent. Does not cause hyper¬ 
trophy. L. 0*05-0*06 mm. A. olesistus R.B., 1893. 
IV. A. PHYLLOPHAGUS N.SP. ANATOMY OP THE ADULT. 
Measurements. $, L. 0-845-0-92 mm.; a, 51-53 (0, 11-3-16-5) 2 ; y, 20-5-21. <£, L. 0-88- 
0-90 mm.; a, 48-52 (0, 12-6-13); y, 16-19. 
Cobb's formula: 
n 1*3 (6-8) 9 ? 70 95-5 
+ 1-2 (1-6) 1-8 ? 2-1 1-3 
* 1*2 (7-4) 9-9 ? M 93 
° 0-8 (1-4) 1-5 ? 2 1-5 
0-923; 
0-965. 
Body-form (Figs. 1 and 2). The hemispherical head is marked off by a groove. Lateral 
membranes absent. Transverse striae of cuticle 0-0008 mm. in breadth. Tail ends in a mamilli- 
form appendage. Lateral lines (Figs. 4-14, LL) occupy jtth of the circumference. Muscle 
fields each contain five cells in cross-section. 
Alimentary system. The spear (Fig. 1, S), length 0-013 mm., thickens slightly to the 
knobbed base. The oesophagus is divided into anterior oesophagus, bulb, and posterior 
oesophagus (Fig. 1, OA, OB, OP); the bulb is conoid and muscular; the intrinsic nuclei 
form a layer in its surface; the centre is occupied by the usual oval chitinous structure; the 
posterior oesophagus 3 is swollen slightly behind the bulb, narrows as it traverses the nerve 
ring, then increases gradually in width to its junction with the intestine, which is marked 
only by the commencement of the intestinal droplets and granules (Fig. 2, 01); the wall 
of the oesophagus is eosinophil in staining reaction, its lumen circular in the posterior 
section. The salivary glands 3 (Figs. 1, 11 and 12, S.G.) lie dorsal to, and slightly to the right 
of the posterior oesophagus and the commencement of the intestine; they consist of four 
cells arranged in linear series: the duct (Figs. 1 and 6-10, S.D.), containing several nuclei, 
passes forward through the nerve ring, and enters the oesophageal bulb at its posterior end 
• (Fig. 5, S.O.); both gland and duct are basophil. 
1 De Man (1886) employs the following useful contractions: 
Length Length Length 
Breadth L. of oesophagus L. of tail ^ 
Length, L. Maximum breadth, B. 
2 The length of the oesophagus is measured throughout to the posterior end of the bulb, owing 
to the indefiniteness of the function of the oesophagus and intestine. This measurement is given 
as the second figure in Cobb’s formula—in brackets. The formula therefore runs: 
Posterior end of spear, (Posterior end of bulb), Nerve ring, ?, Vulva, Anus. 
3 Cf. p. 169 (1). 
11—2 
