Davainetd Cestode from a Wallahy. G09 



Discussion. 



Fuhrmann, in 1920, separated from theold genus Davainea, 

 Bl., four new genera, limiting the genus Davainea to those 

 small forms possessing a restricted number of segments 

 (-t-ly), small suckers, feeble musculature, regularly alter- 

 nating genital pores, aiul uterine capsules possessing only a 

 single onchos|)here. Three of his new genera comprise 

 only four species, whereas his fourth — RaiUleiina — includes 

 almost 90 species. This genus he characterises as follows : — 

 "Cestodestl scolex arroncli surmoiitc d'un rostre de structure 

 simple, arme d'une couronne (loul)le (raremeut simple?) de 

 crochets uombreux, petits et d'luie forme speciale. Ventouses 

 plus ou moins arrondies, entourees de plusieurs rangees 

 de petits crochets ou spicules, cadues ou persistant pendant 

 toute la vie. Pores genitaux unilaterauxou irregulierement 

 alterues. Uterus manquant dans les proglottis murs ; a sa 

 place des capsules parenchymateuses reufermant une ou 

 plusieurs onchospheres." 



He further subdivides the genus RailUetina into four sub- 

 genera, basing his differentiating characters ou the position, 

 unilateral or irregularly alternating, of the genital pores, and 

 on the number of onchospheres, single or more, contained 

 in each uterine capsule. 



Referring the species described above to this new grouping 

 of the Davaineas, it is seen that it belongs to the genus 

 RailUetina and to its subgenus Paroniella. This subgenus 

 is characterised by having unilateral genital pores and the 

 uterine capsules contain only a single ouchosphere. 



From the available literature dealing with cestodes from 

 Marsupials it appears that sixteen cestode genera have been 

 recorded from this group of Mammals. These cestodes, 

 together with RailUetina {Paroniella^ macropa, sp. n., are 

 practically all Cyclophyllids, only one genus — Bothrio- 

 cephalus — belonging to another oider, namely Pseudo- 

 phyllidea. Of the CyclophvUidcan families all are repre- 

 sented except two — namely, the families Tetrabothriidje and 

 ^Icsocestoididse. 



I wish to express my indebtedness to the Zoological 

 Society of London for the opportunity offered of collecting 

 these parasites at their prosectorium. My thanks are also 

 due to Mr. R. I. Pocock, F.R.S., for valuable assistance in 

 the classification and nomenclature of the marsupial hosts. 



The appeiulcd host list is an attempt towards the com- 

 pilation of all the cestodes which have been described or 



