621 



As far as any oilslnal observations are conceriic-d Moliiis 

 species T. tetragona then rested for a number of years. 

 Jn 1880 Megnln (1880, p. 11!)) mentioned T. echlno.bothrlda as a 

 nonien nudum. In 1881 two parasites of chickens, very similar 

 to If not Identical with T. tetragona, were de.scrlbed as new. 

 Megnln described and ngured T. pchlnobothrUla as new s.pecles 

 with the characters given In the diagnosis above (p. 618.) A 

 careful study of both figures and description shows that the 

 niosl Important characters at present to be considered are Ihi- 

 hooks upon the rostellum, said to be abo'Ut 100 In number, 8 

 It long, the rows of hooks upon the suckers (6-7 rows), those of 

 the .middle row being the largest; genital pores Irregularly al- 

 ternate; eggs 90 IX In diameter, spherical, arranged In groups 

 of 6-7 In roundish egg capsules. 



In March of the same yeari (1881) Plana (1882, pp. 387-391, I 

 plate) presented a paper before the Accademla delle Sclenzel dl 

 Bologna, In which he described as a new species T. bothrlop- 

 lltls, a cestode which he found causing serious damage to pf>ul- 

 tiy, producing tubercles In the Intestine. The chief zoological 

 characters taken as a l>asls for the species are as follows: 



Head 0.35mm In diameter; retractile hemispherical rostellum 

 armed with hooks (number not given, but evidently ca. 200. 

 form shown In drawing); suckers with seven or eight concen- 

 tric rows of hooks (form a.s per drawing), hooks not all of same 

 size; neck very long, containing ovoid calcareous corpuscles; 

 genital pores unilateral, .situated somewhat below (dlstally) the 

 middle of the lateral margin; cirrus short, pyrlform; eggs in 

 cffff saos. 



Plana states that Illvolta and Delprato (In Ornltojatria, 1880, 

 T. I., f. na— not accessible to me) picture the head of a cestode 

 which produced similar nodules In the Intestine of a chicken. 

 I'lana found 2 cysticercoids In Helix (whether In It. carthu- 

 sianella or H. maculosa Is not clear to me) which agree quite 

 closely with the head of the parasite found In chickens; no 

 experiments were made to demonstrate that thisi cystlcercold 

 Is the larval form of the worm In question, but their specific 



iThe date of publication of the volume for 1881 Is given upon 

 the cover as 1882, but a preliminary notice of this paper ap- 

 peared In the Rendioonto In 1881. This preliminary notice, 

 however, is altogether too Incomplete to hold should the ques- 

 tion of priority be raised between Megnin's T. echlnobothrida 

 and Plana"3 T. bothrlopUtes. Further, as Plana cites Megnin's 

 article In the final paper, Megnin's name must be given prece- 

 dence, should these two forms pro\-e Identical. Plana's T. 

 bothrlopUtes of 1881 Is to all Intents and purposes a nomen 

 nudum, and his species T. bothrloplltis should be dated 1882. 



