| OCR Text |
Show 124 PROF. G. B. HOWES ON THE AZYGOS [Feb. 21, of the adult. In Bombinator, however, despite the persistence of both renal portal and azygos veins, this continuity is eventually lost. In the specimen of the C o m m o n Frog under consideration it persisted, Fiff.l, a.c icj. - J'.Ct The venous system of an adult of Bana temporaria (2), showing a persistent azygos (posterior cardinal) vein. Fig. 1. Ventral aspect. The vena cava inferior in part removed, and the left kidney turned slightly inwards to display its external dorsal border. Fig. 2. Left kidney, dorsal aspect. Magnified If times. a.c, Vena cava superior; cp, azygos (posterior cardinal) vein ; d.l, dorso-lumbar vein ; il, iliac vein ; od, oviducal veins ; ov, ovarian veins ; p.c, cut ends of vena cava inferior; r.a, venaj renales advehentes; s.v, sinus venosus; ur, ureter. and the anastomosing trunk received (or gave off) renal branches. This fact is the more surprising, in that in Pelobates the separation takes place before metamorphosis, at a period when the anterior segment of the cardinal vein is but feebly developed1. 1 Hochstetter, iv. p. 162. |
