330 REPORT — 1851. 



The genera Lycidice, Aglaura and (Enone, are distinguished readily from 

 all other Annelids by, the existence o{ four styles, two on either side of the 

 anal outlet. It is not a little to be wondered at that such exact observers as 

 Audouin and Milne-Edwards should have overlooked this most peculiar con- 

 formation. In all other respects the portraits of these worms given by these 

 distinguished authors in Crochard's edition of the ' Regne Animal,' are 

 faithful and characteristic. These genera, remarkable for the beauty of 

 the curves into which their very elongated bodies are thrown during loco- 

 motion, frequent, in search of food, all those situations in which the Euni- 

 ciadce are found. To the latter family they bear an intimate resemblance in 

 the structure of the jaws of the proboscis. Like that of Eunice, this organ 

 is short and armed with jaws of four separate plate-like pieces on either side 

 (fig. 55 a). The edge of each element presented towards the median-line is 

 denticulated with recurved short serrations. The two inferior portions are 

 drawn into the shape of a reaping-hook, the base being toothed. The descrip- 

 tion now given applies more especially to Aglaura fulgida of Savigny. 



In Lycidice Ninetta (fig. 54) the jaws comprise three elements, having each 

 a peculiar conformation. The inferior jaw is a flattened club-shaped instru- 

 ment adapted for slicing ; the next displays the form of an acutely-pointed 

 reaping-hook, while the next is bluntly serrated. These three peculiarly con- 

 structed instruments are evidently designed for three distinct mechanical pur- 

 poses in the seizure and mastication of food. In another species of Lycidice, 

 hitherto undescribed, the proboscis is furnished with jaws which are com- 

 posed of pyramidal pieces only, and adapted exclusively for piercing. The 

 hook-like and serrated elements are wanting. This species is found only on 

 certain Alga, and its food is probably of an exclusively vegetable nature. 



The proboscis in the genus (Enone coincides closely in character with that 

 of the two preceding genera. The jaws occur under the shape of curved 

 denticulated plates. In the conformation of the alimentary canal in these 

 genera there is nothing peculiar to be noticed. The oesophagus is long, 

 and terminates where the biliary segment begins. At this point it is em- 

 braced by a large circular vessel, by means of which a communication is 

 established between the ventral and dorsal moieties of the circulating system. 

 It is strong-walled and muscular. It is destitute of glandules ; these are 

 limited to the parietes of the proboscis. 



In the biliary intestine of this, as indeed of nearly all other Annelids, 

 the stomach proper and intestine are confounded both in structure and in 

 function. It is not improbable from the disproportionately extensive tract 

 of surface over which this yellow glandular organ is distributed in the Anne- 

 lida, that the product secreted by it may unite the qualities of the gastric 

 and biliary digestive fluids. On the possibility of such fusion of functions, 

 observations have already been adduced. 



Dr. Johnston observes with reference to the proboscides of the Nereids, 

 that "the pattern after which they (prickles of the proboscis) are arranged, 

 varies in some species ; but it is almost impossible to define those variations 

 in words, and the character fails us in the nearest allied species, where only 

 it is required. Such is also the case with the number of serratures along the 

 falcate edge of the jaws; though the character is one not to be neglected ; 

 but from the peculiar shape of the jaw, I have sometimes found a diflSculty 

 in determining the exact number of these serratures ; and in other instances 

 have had a doubt whether one or two of them, from their obsoleteness, ought 

 to be reckoned*." These difficulties do not accord with my experience. 

 With a good microscope it becomes quite clear always that different species, 

 however nearly allied, are characterized by proboscidian jaws of distinctive 

 * Annals and Magazine of Natural History, vol. iv. 



