NO. 1 HARTMAN : POLYCHAETOUS ANNELIDS 133 



Family Lumbrineridae 



The Lumbrineridae, as herein restricted and as distinct from the 

 Arabellidae (new name, p. 170), constitute a large group of species, be- 

 longing to few (4) genera, uniquely uniform in external features be- 

 cause of simplicity and reduction of many morphological parts. More 

 than any other of the polychaetes, they resemble oligochaetes lacking a 

 clitellum, but the setal structures and parapodial lobes are proportionate- 

 ly much more developed ; also, anatomically their affinities are with the 

 Eunicidae. The prostomium is reduced to a simple, more or less conical, 

 or depressed spherical, lobe without appendages (but with 3 minute an- 

 tennae in Augeneria Monro), sometimes with a transversely linear series 

 of dark ej^espots along its posterior margin. The first 2 segments are 

 simple, apodous rings. Succeeding segments are more or less cylindrical 

 to somewhat depressed, provided with laterally produced, uniramous 

 parapodia, moderate to small in size. 



The parts of the proboscis are paired throughout, typically consist of 

 4 pairs of dorsal, paired, maxillary plates, numbered maxilla I (or for- 

 ceps) to maxilla IV; plates II to IV have few or more numerous denta- 

 tions, or are simple. The forceps are basally attached to a pair of flat- 

 tened, broad carriers without a median piece on the ventral side, such as 

 characterizes the Arabellidae. The ventrally located mandibles consist of 

 a pair of flat plates, fused along their median line, sometimes for their 

 entire length (Ltimbrineris acuta, p. 145), or decreasingly so to only a 

 short, anterior portion of it. The mandibles and maxillae together consti- 

 tute a more or less chitinized (sometimes also partly calcified) portion 

 of an eversible, masticatory apparatus, often strongly developed. 



Parapodia are usually simple, often inconspicuous, short outpocket- 

 ings of the body wall, with a short, fleshy portion provided with an acicu- 

 lar fascicle and immediately posterior to it a vertically disposed, fan- 

 shaped fascicle of setae and/or hooded hooks. The anterior and posterior 

 portions of this fleshy lobe may be more or less prolonged to form the 

 presetal and postsetal lobes, which in some instances form structures of 

 unique specific significance. Only one, usually the postsetal, lobe may be 

 prolonged, causing a unilabiate condition, or both presetal and postsetal 

 lobes may be prolonged to form a bilabiate condition. In some, both lobes 

 may remain fairly constant throughout. In Ninoe Kinberg the postsetal 

 portion enlarges in some segments, comes to be palmately lobed to form 

 branchial structures. The supporting rods, or acicula, may be pale straw 

 colored, yellow, amber, to dark brown or even black; in a few species 



