DESCRIPTIONS OF GENERA AND SPECIES 435 



74 on XXI. Between male pores, eight setae. Two pairs of genital papillae as in last species. 

 Gizzard not recognizable ; three accessory gizzards behind. Hab. — Loqwilocun, Samar. 

 Neither of these species difiPers widely from P. horsti. The chief difference appears 

 to be the rudimentary gizzard of the two last species (only to be seen in sections), 

 contrasting with the conspicuous gizzard of P. horsti. 



Genus Pebionyx, Peeeieb. 



Syn. Megascolex, Vaillant (in part.). 



Definitioit. Bing of setae continuous, present upon all segments of clitellum. 

 Clitellum, XIII-XVI (XVII, XIX). Male pores closely approximated, with or 

 without specialized setae in their neighbourhood. INo caeca. Dorsal pores 

 commence V/VI. Spermathecae, two or three pairs in (VIl) VIII, IX. 

 D'ephridia paired. Spermiducal glands lobate. 



This genus has been referred by Bbnham (1) to a distinct family; but in my 

 opinion this step is as erroneous, on the one hand, as is Vaillant's refusal, on 

 the other hand, to allow it generic separation from Perichaeta. 



Benham indeed, in his phylogenetic scheme (p. 380) puts the Perionycidae nearly 

 as far away from the Perichaetidae as is possible ; they only come together at the 

 very commencement of the series, diverging immediately. But this is due to his 

 separating (in my opinion quite wrongfully) certain of my Cryptodrilidae from others. 

 No doubt Perionyx does bear resemblances to Plutdlus, Pontodrilus, &c.; but if, as 

 I think we inevitably must, we regard Plutellus as nearer to Typhoeus than to 

 Eudrilus, and place Perichaeta in the neighbourhood of the two former genera, it 

 is unnecessary to assume that the complete circle of Perionyx_ has been independently 

 acquired, even granting for the moment that that condition is secondary. 



Besides the points mentioned in the above diagnosis of the genus, it may be 

 distinguished from Perichaeta or from Megascolex by a number of other characters; 

 in the first place, there are no' specially thickened septa ; the presence of these 

 structures is so very usual that their absence gets, perhaps, an undue importance. 

 In having paired nephridia, this genus resembles Diporochaeta, and differs from all 

 other Perichaetidae. 



The most interesting fact in the anatomy of the genus concerns the genital setae 

 in the neighbourhood of the male pores; in two species, at any rate, there is 

 a group of long setae with a very marked ornamentation at the free extremity near 



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