636 MR. F. E. BBDDARD ON 



gonads were passed to the exterior through those tubes. However, 

 the uterus is actually present in this form. 



From the above account of the external characters and internal 

 anatomy of this worm we maj' deduce the following brief 

 resume : — 



Length 80-60 mm., diameter 1 mm.-2 tnm. Posterior region of 

 the body 'markedly differentiated in fully adtdt examples by its 

 great thickness, but anterior end not so thin as in many forms. 

 Terminal segment with deep slit-like depression always ptreseivt. 

 Scolex tmarmed with rudimentary rostellum. Suckers unanned 

 a/)id sunk within the head, which is tetragonal in section. No neck, 

 segmentation beginning at once ; the anterior five or six proglottides 

 ■wider than scolex and seeming to form a hood into which it can be 

 jxirtly retracted. Proglottides variable in proportions of length to 

 breadth. In many examples all of them, save the last fevi, broader 

 than long. In others some of anterior segments longer than broad. 

 Dorsal and ventral excretory canals not parallel, the tv)o dorsal 

 being nearer together than the tioo ventral ; in addition to these, two 

 lateral narrower canals on each side. Cortical layer as thick as 

 medullary. Genital pores alternate irregularly, the preponderance 

 being on one side, nea,r to anterior border of proglottid,. Testes 

 numerous, posterior to and at the sides of ovary. Ovaries in 

 anterior part of proglottid commencing shortly after anterior border. 

 Genital ducts pass between dorsal and ventral water tubes. Vas 

 deferens coiled; no obvious seminal receptacle or seminal vesicle. 

 Uterus sac-like, with branches ; ultimately disappearing, the eggs 

 being imbedded singly in the pai-enchyma. Occasionally traces of 

 uterus inform of sacs containing two or three ova 2)ersist. 



Hab. Small intestine of Tamandua tetradactyla. 



We may now consider the systematic position of this Cestoid. 

 The lateral position of the genital pores, the unarmed scolex, the 

 four suckers without appendages or hooks, the anterior position 

 of the cirrus pouch, the absence of more than a suggestion of a 

 pseudoscolex, show that this worm is to be referred to one of the 

 three families Anoplocephalidae, Hymenolepididse, or Tseniadse, 

 of Ransom's systematic table * (which is with slight differences 

 the same as that of Fuhrmann t). From many of the numerous 

 genera contained in the first two of these families and the very 

 few genera of the last, the present worm is to be differentiated 

 by the following assemblage of characters : — scolex unarmed, no 

 neck ; genital organs one set to each proglottid, with irregular 

 pores ; testes numerous, posterior in position ; uterus disappears ; 

 eggs imbedded singly in parenchyma. 



The chai-acters of the worm rather suggest the Anoplocephalidse, 

 particularly, of course, the unarmed scolex and the absence of a 

 " neck." But there is no genus in this family to which it can be 

 referred. The nearest is Linstowia, in which the genital pores 

 are alternate, the eggs are imbedded singly, and the cortical layer 



* Bull. U.S. Nat. Mils. no. 69, 1910. 

 t Zool. Jalii-b. extra vol. x. 1908. 



