8 PROCEEDINGS OP THE ISTATIOlSrAL MUSEUM vol.75 



no question of the close relationship of the two worms. Hastospiculum 

 gouldi Yorke and Maplestone 1926, is a small worm with a number 

 of oral papillae, small spicules, and a different arrangement of the 

 caudal papillae of the male. Filaria hijnnnata Linstow 1899 is also 

 clearly a member of this genus, and should therefore be known as 

 Hastospiculum bipinnatum; H. gouldi may possibly be identical with 

 this species. 



THYLACONEMA, new genus 



Generic diagnosis.— Theiaziidhe : Body comparatively coarse, taper- 

 ing at each end. Cuticle coarsely annulated, the annulations pro- 

 vided with numerous backward projecting spines, most marked on 

 the anterior half of the body. Mouth provided with a distinct and 

 nearly square buccal cavity, the anterior borders of which close 

 together slightly and have four very slightly salient lobes. Esopha- 

 gus short and straight, not divided into two parts, and its demarcation 

 from the intestine indistinct; the esophagus and intestine together 

 form a straight narrow tube of uniform diameter for the whole length. 

 Vulva in the esophageal region, the vagina an elongate saclike struc- 

 ture; opisthodelphic. Tail of female a short, narrow, fingerlike 

 structure. Male uncertain; specimen found with type female lacks 

 anterior end and can not be positively identified as the mate of the 

 female worm. The generic characters of this specimen are as follows: 

 Tail with broad and relatively short alae with a few large peduncu- 

 lated preanal papillae and a few large and several small postanal 

 ones. Spicules unequal, both long and slender; gubernaculum 

 present. Parasites of the peritoneal cavity of birds. 



Type species. — -Thylaconema sigmura, new species. 



THYLACONEMA SIGMURA, new species 



Figs. 12 to 15 



Specific diagnosis. — Thylaconema: 



Male found associated with the type female lacks anterior end, and 

 so can not be definitely diagnosed as the same species or even genus, 

 although it probably is the same species. Maximum diameter 270/i; 

 tail (fig. 15) with broad and relatively short alae, forming a bursa- 

 like structure 400ai long and about 300m wide, marked with fine stri- 

 ations; two pairs of large pedunculated preanal papillae, one pair at 

 the level of the anus, two pairs of postanal ones, and three or possibly 

 four pairs of small ones near the tip of the tail. Anus 175m from tip 

 of tail. Spicules long and slender, the right one 1.35 mm. long, the 

 left one 590m long; gubernaculum present, consisting of two conver- 

 gent chitinized bars connected by a delicate membrane. 



Female about 15 mm. long with a maximum diameter of about 

 400m. Diameter of head about 65m, the diameter very gradually 

 increasing posteriorly and more rapidly decreasing again near the 



