410 THE ANNELIDA POLYCHAETA. 



Synonymy of Genera. 



Leiooephalus Quatrefages (non Gray, 1827) is the same as Leiochone Grube, 

 as is also Clymenura Verrill. 



Praxillela Verrill is regarded as synonymous with Iphianissa Kinberg. 



Clymene Savigny, being preoccupied (Oken, 1815), has been replaced by 

 Euclymene Verrill, and Praxilla Malmgren, antedated by Praxilla Reichenbach 

 (Aves, 1853), has been replaced by Iphianissa Kinberg. 



Chrysothemis Kinberg (non Berendt, 1845), Sabaco Kinberg, and Mal- 

 danopsis Verrill are synonyms of Asychis Kinberg. 



Neco Kinberg belongs in the subfamily Lumbriclymeninae near Notoproctus, 

 but is not completely enough known to be equated or placed precisely. 



In the Nichomachinae, according to Arwidsson, who has examined the types, 

 belong Mandrocles Kinberg {M. architedus) , a form with long capillary setae, 

 and Mylitta Kinberg (M. quinquemaculata) . The latter name is preoccupied 

 (d'Orbigny and Reclus, Moll., 1850) and may be disregarded. 



Johnstonia Quatrefages probably belongs in the tribe Euclymenini of the 

 Euclymeninae, but its precise identity is as yet in doubt. 



Axiothea Malmgren, being preoccupied (Pascoe, 1864), gives way to Par- 

 axiothea Webster (1879), of which Clymenellaand Axiothella of Verrill are also 

 sjoionyms. 



Petaloproctus Quatrefages. 



Hist. nat. anneles, 1865, 2, p. 247; Arwidsson, Zool. jahrb. Suppl., 1907, 9, heft. 1, p. 113. 

 Nicomachella Levinsen, Vidensk. meddel. foren. Kjoben., 18S4, 1883, p. 141. 



Petaloproctus crenatus, sp. nov. 

 Plate 73, fig. 3-7. 



In the type, shrinkage has resulted in producing marked constrictions 

 between the somites, the body thus presenting an almost moniliform appearance. 



No non-setigerous somite in the posterior region. Penult and antepenult 

 somites abruptly much shorter than those preceding. The penult somite not 

 clearly separated from the anal. Only a small fascicle of capillary setae on the 

 ultimate somite, no uncini occurring. 



Anal somite bearing setae of the usual type at the anterior end, clavately 

 enlarging caudad, with the dorsal line convex and the ventral slightly concave. 

 The free border or hmbus of the anal funnel is dorsally almost obliterated, being 



