38 BULLETIN (30, UNITED STATES NATIONAL MUSEUM. 



of the strobila, especially in the last 15 to 25 segments. This organ, 

 which is located in the region of the genital pore, is ampuUiform, 

 ellipsoidal, and filled with spermatozoa; from it may be traced the 

 long sinuous vas deferens. The last three to eight segments contain 

 fully developed eggs, which are few in number. They seem to be 

 scattered in the parenchyma or contained in a cavit}' which has 

 pushed aside the parenchyma, and they so fill the segment that no 

 other structures are visible except the seminal vesicle [receptacle]. 

 They are spherical, with three envelopes, and measure 45 to SOju, in 

 diameter. The outer membrane is smooth and transparent; between 

 it and a second membrane of double contour is a granular mass. The 

 third membrane is that which immediately surrounds the oncosphere. 

 The oncosphere measures 25 to 30/* in diameter; its hooks, 18/* in 

 length ; the diameter of the second membrane is 32/x. 



Railliet and Lucet (1899a, pp. 144—146) have reported the discovery 

 of tapeworms in turkej^s which they consider identical with Taenia 

 cantaniana. These worms x^resent the following characters: Length, 

 1.9 to 3.2 mm. ; maximum width, 200 to 320/x. Strobila consists of 

 50 to 88 segments. Eggs fully formed in the last 6 to 8 segments, 

 also apparent in less fully developed condition in preceding segments, 

 so that the last 15 to 18 segments may be looked upon as gravid. The 

 eggs are spherical with three envelopes, the internal and external one 

 the thicker. The external envelope has a diameter of 54 to 57/*, the 

 middle. 39 to 42/* ; the internal one surrounding the oncosphere is 29 

 to 30/* in diameter. The hooks of the oncosphere are 12 to 13/i in 

 length. 



These authors are of the opinion that Davainea oligophora Magal- 

 haes is identical with Tmnia cantaniana Polonio in view of the strik- 

 ing similarity of the figures of Polonio and Magalhaes. 



Magalhaes (1899b, pp. 480-482) refused to accept the view of 

 Railliet and Lucet on the ground that Polonio's description is too 

 incomplete to give the species Tcenia cantaniana any standing. Con- 

 trary to the opinions of Stiles and Magalhaes, it seems to me that 

 Railliet and Lucet are correct in considering Tcenia cantaniana a 

 recognizable species, and I believe that the forms which I have studied 

 are sufficiently similar to Polonio's description and figure to justify 

 their identification as Tcenia cantaniana. They also agree so closely 

 with Magalhaes's description of Davainea oligojjhora that there is 

 little doubt of their identity with that species. 



The lack of hooks in all specimens which I have examined is one 

 ppint of difference from Davainea oligophora^ but as Magalhaes 

 found hooks in but few cases and states that they are very instable 

 and usually absent, this difference is not very remarkable. In other 

 respects the head is entirely like that of Davainea oligopliora^ though 

 I have found it slightly larger than described by Magalhaes. There 



