NEREIDS. 257 



Geratocephale, Malmgren. Without the upper tongue or lobe, but with lip-lobes 



and middle tongue, the inferior division as in Nereis. 

 Tylorlnjnchus, Gr. Only the upper and middle tongues of the feet present. 

 The proboscis beset with hard papilla. 



B 2 . The dorsal cirrus in certain segments furnished with branches (an arbuscle). 

 Ex. Dendronereis . 



In his 'Philippine' Annelids (1878) he groups the Nereids under the family Lycoridea 

 — with Nereis and Dendronereis as sub-families. He relies on the condition of the proboscis 

 as the basis of his subdivisions, e.g., Leptonereis, Geratonereis, Platynereis, Lycoris, and 

 Perinereis. He had previously reviewed the group on similar lines, his main divisions 

 agreeing with those of Ehlers ; but he clearly indicates that Lycastis has two bristle- 

 bundles in the foot, though it appears to be simple. 



Levinsen (1883) made the Nereids (Lycoridaa) the first family of his Syllidiformia 

 vera, whereas Benham places them as the sixth family of his Nereidiformia. There is less 

 objection to the associations of the former than to those of the latter. He follows the 

 previous authors, Kinberg, Grube, Malmgren, and Ehlers, in his generic and specific 

 characters. 



R. Horst 1 (1889), in dealing with the Nereids belonging to the sub-genus Perinereis, 

 follows Grube in showing that the lateral dorsal paragnathi of the basal ring of the 

 proboscis (Group VI) are all, or some of them, transversely ridge-shaped, the remaining 

 paragnathi being conical or pin-shaped (pectiniformes, Kinberg) or compound. The feet 

 are all of the same structure, or those of the posterior region enlarged. The group comes 

 under Kinberg's Aretidea, but not his genus Perinereis. Horst includes Nereis cultrifera, 

 Grube, under this series. 



De St. Joseph, 2 in 1898, adopted the classification of Kinberg, founded mainly on the 

 condition of the paragnathi, though the primary divisions are based on the presence or 

 absence of dendritic branchiae. In addition he uses the condition of the buccal segment 

 and the uni- or biramous nature of the feet. It is a question how much importance can 

 be attached to this method of classifying, though it may be useful. The British species 

 would chiefly fall under the fifth group of the second great division, viz., Nereis, 

 characterized by separate, horny, conical paragnathi, Alitta and Hediste, p.p., having all 

 the groups complete, whilst Group V or Groups V and VI are wanting in Nereilepas, 

 Hediste, p.p., and Praxithea. In Eunereis, again, all the groups except VI are absent. 

 In the sixth division are those in which there are separate, horny, conical, and transverse 

 paragnathi, all the groups being complete in Lipephile, Mgrn., Hedyle, Mgrn., Hediste, 

 Mgrn. p.p., Stratonice, Mgrn., and Nereilepas, Blv. sensu Johnst. In the eighth section 

 the horny paragnathi are very small, numerous, and ranged in rows, e.g. the genus 

 Platynereis including Leontis of Malmgren. As genera occur under more than one head, 

 confusion is apt to arise by too strict adherence to such a classification. 



Gravier (1901), in his < Annelids of the Red Sea,' followed in the lines of Grube and 

 Kinberg, that is, made the arrangement of the paragnathi when present, and, in their 

 absence, the structure of the feet, the foundations of his genera, except in the case of 



1 ' Notes from the Leyden Museum/ vol. xi, pis. vii and viii, 1889. 



2 ( Ann. Sc. Nat./ 8 e ser., v, p. 283 et seq. 



90 



