MOORE: HIRUDINEA OF SOUTHERN PATAGONIA. 685 



GLOSSIPHONIA MICH^ELSENI (Blanchard). 



(Plate L, Figs. 13, 14.) 



Among the peculiarities of the reproductive organs (Plate L, fig. 14) 

 the following are noteworthy. There are epididymal loops (sperm sacs) 

 formed by the vasa deferentia as in G. duplicata, G. stagnalis, etc., and 

 usually reaching beyond ganglion XVIII. In one respect they differ 

 strikingly from those of G. duplicata and as closely resemble G. simplex, 

 viz., the vasa deferentia after turning remain of extreme tenuity until 

 reaching XV or XVI, that is, for about half the length of the loops, and 

 then suddenly enlarge into the sperm reservoirs. This is true of all of a 

 considerable number dissected. Before entering the prostates, the duct 

 is thrown into several deep folds, which extend anterior to the atrium even 

 into somite XI. 



In the form of the alimentary canal (Plate L, fig. 13), as indeed in 

 many other respects, this species closely resembles Glossiphonia nephe- 

 loides (Graf.) (= G. elongata Castle), a not uncommon species in Penn- 

 sylvania, New Jersey, and Massachusetts. A striking difference in the 

 digestive tract, however, is the entire absence of the large gastric caeca, 

 which in other Glossiphoniae arise in XIX, and in G. nepheloides extend, 

 according to Castle, through two somites. 



The mouth, which is of remarkably large size, is in somite III. The 

 pharynx, which, when retracted, reaches from VIII to a point just caudad 

 of the male pore, is stout and may be extended to an unusual distance, 

 in some cases to nearly one third the length of the body. It is nearly 

 cylindrical, but tapers somewhat abruptly at the free end, which is termi- 

 nated by nine larger muscular denticulations, arranged in three sets of 

 three each and alternating with three smaller ones. Three longitudinal 

 muscular ridges continue these for the entire length of the pharynx and 

 give to its lumen the usual triangular form. They terminate at the point 

 of entrance of the ducts of the pharyngeal glands in XII or XIII. As 

 in most small glossiphonids of the Helobdella group, these glands are 

 strictly paired. In this species they consist of a very few unicellular glands 

 of large size arranged in a loose group confined mainly to XII and XIII, 

 though occasionally extending somewhat into the immediately adjacent 

 somites. The ducts are in one pair, of large size and strongly muscular. 



A short oesophagus gradually widens into the thin-walled, somewhat 



