NEMATODES, MOSTLY AUSTRALIAN AND FIJIAN. 



By N. a. Cobb. 

 (Plates I. -VII.) 



Introductory Note. 



The following pages contain descriptions, accompanied by about one hundred 

 and seventy figures, of eighty -two species of Nematodes, of which about half have 

 not been hitherto described. In a number of cases the anatomical details have been 

 worked out in a manner worthy the attention of the morphologist. 



Fig. 1. — Diagram in explanatioa of the descriptive formula used for Nematode worms ; 6, 7, 8, 10, 6 are the transverse 

 measurements, while 7, 14, 28, 50, 88 are the corresponding longitudinal measurements. The formula in this 



case is : — 7- 14- 28- 50' 38' 



6^ T- 8- 10- 6"- 



The unit of measurement is the hundredth part of the length of the worm, whatever that may be. The 



measurements become, therefore, percentages of the length. 

 The measurements are taken with the animal viewed in profile ; the first is taken at the base of the pharynx, the 



second at the nerve-ring, the third at the cardiac constriction, the fourth at the vulva in females and at the 



middle (M) in males, the fifth at the anus. 



Genus MONONCHUS, Bastian. 

 The genus Mononchus is composed of herbivorous free-living Nematodes, not 



1 • ,1 p T 2-5 7-6 25- 'eO' 90- j 2-5 7-8 25- — M— 90- 



marine, havmg the average lormulBe 2-5 2-8 s-e %■% — F ^"""- ^-iid- 2-6 2-8 a-e — Ts — 2- 2(-)mm. 

 They are readily recognised by their capacious pharynx, containing from one to three 

 commonly conspicuous teeth, whose function is, in conjunction with certain minute 

 file-like or rasp-like areas on the wall of the pharynx, to masticate the food, which 

 consists of fresh and succulent vegetable matter, such as rootlets, or the tissues of 

 aquatic or sub-aquatic plants, or the protected tissues found among the sheaths 

 of the leaves of certain land-plants. The thick transparent cuticle of these worms 

 is destitute both of hairs and striae. The neck is sometimes almost cylindrical, 

 but is usually conoid, and invariably ends in a truncate head, which in one species 



