DESCRIPTIONS OF GENERA AND SPECIES 653 



Hypogaeon is a name which must be dropped as it is apparently synonymous 

 with Lumbricus (s.L). 



In addition to the points mentioned in the definition of the species given above 

 the following may be noted. The calciferous glands, like those of Pontoscolex, are 

 completely detached, and stand out from the walls of the oesophagus ; they are 

 subconical in form, the apex being directed away from the gut. After the last thick 

 septum there is one which is considerably thinner, but which is closely attached to 

 those in front and covers them. 



Genus Pontoscolex, Schmaeda. 



Syn. Lumbricus, Fe. Mullee (in part.). 

 Urochaeta, Peeeiee. 



Definition. Setae ornamented, bifid at the free extremity, alternate in posterior 

 segments. Male pores X3^XXI. Posterior nephridia with glandular diverticula ; 

 peptonephridium present. Calciferous glands three pairs. Spermathecae, two 

 or three pairs in front of testes. 



The first really adequate description of this genus is due to Peeeiee (5); the 

 memoir referred to contains an exceedingly elaborate account of the anatomy of 

 ' Urochaeta,' the section dealing with the organs of circulation being especially full 

 and detailed ; more recently Hoest (17), Rosa (1), and I myself (28, 45, 61, 71), 

 have contributed to the knowledge of the genus. 



The generic name ' Urochaeta ' was first introduced by Peeeier (3), two years before Ms 

 exhaustive memoir upon the genus appeared ; at that time the French naturalist -was unaware 

 of the fact that this worm had been previously discovered and described by Feitz Mullee as 

 a species of Lumbricus. Though Peeeiee was, of course, perfectly justified in creating a new genus 

 for the 'Lumbricus corethrurus' of Mullee, I showed myself (28) that in reality the name which 

 ought to be applied is Pontoscolex; for a study of the type-specimens of Pontoscolex arenicola of 

 Schmaeda led to the conclusion that some of them must be referred to the same genus as 

 Urochaeta. Schmaeda's diagnosis of the genus is as follows : — 



' Quatuordeoim series setarum alternas binas. Clitellum. Maricolae.' 



From this almost useless definition hardly anything could be inferred as to the systematic 

 position of Pontoscolex. And the rest of the information which Schmaeda gives is not of much 

 more use. Rosa, however (20), influenced, no doubt, by the 'quincuncial' arrangement of the 

 setae, rightly referred Pontoscolex to his family G-eoscolicidae. Vaillant also, though declining 

 to commit himself (8) as to the proper place in the system which the genus should occupy, 

 called attention to its resemblances to Urochaeta. 



