MELANENCHYTRAEUS SOLIFUGUS 



The pharynx builds a dorsal appendage of the oesophagus, in the 2nd 

 and in the beginning of the 3rd segment (Fig. 3 pJi) ; its dorsal part gives 

 insertion to a system of muscular bundles, which suspend this organ to the 

 walls of the foremost four body-segments. Fig. 4 gives, in a somewhat 

 schematic form, the graphic reconstruction of these muscles, made from 

 a series of sagittal sections. The system consists of an anterior and posterior 

 group. The former arises from the dorsal wall of the ist and anterior end 

 of the 2nd segment ; the other is more complex and offers two knots, to 

 which the bundles from the dorsal wall of the 3rd and 4th segments, and a 

 bundle from the ventral wall of the 4th, converge. 



The part of the alimentary canal which follows on the pharynx, and 

 may be called cesopkagus, offers no notable widening, and is continuous 

 without partition with the rest of the gut. The long cilia of the intestinal 

 epithelium are clearly shown in my preparations (Fig. 5 ei). 



I have found in the gut some specimens of an Infusorium of the genus 

 Anoplophrya (Fig. 18); I could not see cilia on its surface, although the 

 long cilia were well preserved on the intestinal epithelium in the same 

 section. The intestine of the same specimens of the worm contained a 

 number of ovate, brown bodies, closed in a thin membrane, and filled with 

 clear spherules (Fig. 19 <a;) ; some of them were cut by the microtome knife 

 (Fig. 19^), and showed in each spherule a grain (the nucleus?), coloured 

 by carmine. I don't know whether these bodies have any relation to the 

 Anoplophrya ; they might be incapsulated germs of the parasite. 



The intestine, and more markedly its posterior part, is filled with very 

 fine crystalline mineral detritus, which seems to be the ordinary food of this 

 worm. 



The cells of the chloragogen (Fig. 5) are very long, and build a dense 

 coating to the intestine. 



In the segments 4-8, the most part of the body-cavity is filled by 

 unicellular glands (Fig. 1 1 gt) ; their very thin excretory prolongations form 

 numerous threads directed towards the ventral side, which can be easily 

 followed on the sections to the sides of the ganglion chain. Their thinness 

 and flexuous course make it extremely difficult to follow them to their end 

 on the surface of the skin. I believe that they converge towards the bundles 

 of chaetae of the ventral series. As Mr. Michaelsen writes me, these glands 

 may be regarded as morphological equivalents to those gland-cells which 

 in other Enchytraeids are related to the chaetae of the genital segments. 

 In Melanenchytraeus, I don't think that these glands have any relation to 

 the functions of reproduction, because I find them no less developed in 

 immature specimens. 



In some anterior segments, and peculiarly in the 9th and loth, there 

 are, between the nephridium and the body- wall, clusters of cells (Fig. 12 x) 

 whose plasma is filled with very minute and strong refracting granules, 

 rendering them obscure in transmitted light, white in incident light. These 

 cells are not clearly outlined, and in the middle of each a small round nucleus 



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