228 ILLINOIS BIOLOGICAL MONOGRAPHS [228 



stated that this species belonged to the Ichthyotaenia. In a footnote he 

 says, "Herr Prof. Parona hat mir die Original-exemplare der Art in 

 uneigenniitzigster Weise zur Verfiigung gestellt, so dass ich die Zuge- 

 horigkeit derselben zu der Gattung Ichthyotaenia feststellen konnte." 

 Schwarz (1908:33-35) had no specimens of this species for examination. 

 He rewrote Parona 's description but was able to add nothing new. He 

 believed this form to be a species of Proteocephalus and called attention 

 to the fact that the lower part of the uterus in Parona 's drawing was 

 probably the ovary and that the testes would be found in the anterior 

 region of the proglottid where they were frequently difficult to see. 

 La Rue (1911:474) stated that this species belonged with the genus 

 Ophiotaenia and gave a few of its characters. 



Thanks to Professor H. B. "Ward who secured this material from 

 Professor Parona for the purpose of this study the writer has been able 

 to give this species a more careful description than has hitherto been 

 attempted. The material consists of about a half dozen pieces among 

 which no head could be found. This material is labelled ' ' Arynchotae- 

 nia trimeresuri Par., Trimeresurus formosus (Mentawei) ". From it 

 two toto preparations were made. These together with the alcoholics 

 and Parona 's original description form the basis of the following 

 description. 



In the material at the writer's disposal the head, neck and first 

 proglottids were missing. The pieces measured 10, 20, 60 and 70 mm. 

 long by a maximum breadth of about 1.0 mm. Parona in a table gave 

 data concerning the length and breadth of five specimens with heads 

 and five without. The length of those with heads ranged from 12 to 50 

 mm. and the maximum breadth from 0.75 to 0.1 mm. while the headless 

 specimens measured 33-105 mm. in length by a maximum breadth of 

 0.75-1.5 mm. The scolex is spheroidal, has neither hooks nor rostellum, 

 and is broader than the neck. Its diameter is about 0.75 mm. The 

 suckers are prominent and are situated in the anterior part of the head. 

 They are hemispherical, strongly muscular, and have a diameter of 0.16- 

 0.25 mm. The aperture of the sucker is 0.11-0.16 mm. Parona 's draw- 

 ings of the scolex are reproduced (Figs. 141, 142). 



The neck is about three times as long as the scolex. Its breadth 

 varies from 0.25 to 0.5 mm. The first proglottids tho broader than long 

 are not very short. These become successively longer, the last being long- 

 est. The increase in length, however, is not constant because short pro- 

 glottids are to be found between long ones. Nor is the breadth of the 

 strobila constant. Some proglottids are about quadrate while others are 

 2-3-4 times longer than broad. Proglottid limits are poorly defined ren- 

 dering the strobilation indistinct. The angles of the proglottids are not 



