180 T. THOMSON FLYNN 



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9. DESCRIPTION OF FIGURES. 



The outlines of all figures have been drawn with the aid of 

 Zeiss's camera lucida, then enlarged by means of the panto- 

 graph and details filled in by freehand. 



List of Reference Letters. 

 all., allantois. all.cap., allantoic capillaiy. all.&id., allantoic entoderm. 

 all.tite^., allantoic mesoderm, all.pen., penetration of the allantoic meso- 

 derm, all. St., allantoic stalk, all.ves., allantoic vesicle, anin., amnion. 

 ana., anastomosis of the two portions of the smus termmaUs. bil.omjjh., 

 bilamuiar omphalojjleure. cav., cavity contamed hi syncytial nests, 

 ch.mes., chorionic mesoderm, ch.ect., chorionic ectoderm, coel.w., coelomic 

 wall of the allantoic vesicle, cyt., cytoblast (cytotrophoblast). , emh., 

 embryo, ex.coel., extra-embryonal coelome. ex.syn., maternal syncytium 

 of the extra placental area, ex.syn.io., syncytial nuclei of the extra-placental 

 area, g.c, multmucleate giant cell, (jl., gland, cjl.ep., gland epithelium. 

 inf., infiltrated material (? lymphatic) contauied in the cavity of a syncytial 

 nest, ing., material mgested by the plasmodiblast. leuc, leucocytes. 

 mat.cap., maternal capillary, m.ch., margmal chorion, muc, uterine 

 mucosa, muse, muscularis. ph.. plasmodiblast. ph.n., plasmodiblast 

 rmclei. pgin., aggregations of pigment in the jilasmodiblast. plac, allan- 

 toic placenta, pl.syn., maternal syncytium of the placental area, proa., 

 proamnion, syn.n., nuclei of the maternal trophospongia. troph., maternal 

 trophospongia. vasc.omph., vascular omphalopleure. v.otnph., vascular 

 omphalopleure. vit.a., vitelline artery, vit.v., vitelline vein, yk.cav., 

 yolk-sac cavity, y.s., yolk-sac. yl.spl., yolk-sac splanchnopleure. 



