Congenital Anomalies of Arteries and Veins 49 



usual, Fleischmann (1815), Macalister (1868), Miura (1898), 

 Pensa (1908). Zumstein (1895) found that the right spermatic 

 opened into the right renal 4 times in 220 observations. 



Renal veins show some tendency to form two or more trunks 

 as the arteries do, but the frequency of this anomaly is not so great ; 

 my series shows a frequency of about 7 per cent. For references 

 on this subject see list under renal arteries above. 



V. PORT^ 



Accessory splenic veins are reported by Blasius (1674), Blan- 

 card (1688), Watson (1838), and Hyrtl (1839). The splenic 

 vein may anastomose with the renal, Lejars (1888), Marian 

 (1901), or with the superior mesenteric, Hyrtl (1859). 



A connection may exist between the superior and inferior mesen- 

 teric veins, Villemin (1912). Tellaux reports finding a superior 

 mesenteric vein opening into the renal vein. A very excellent 

 detailed study of the mesenteric veins in their normal arrangement 

 is given by Descomps (1912). 



V. UMBILICALIS 



Luschka recognized a normal connection between the umljilical 

 and deep epigastric veins, but I believe the first description of the 

 embryology was by Burow (1838). This was confirmed l)y Wer- 

 theimer (1886) and Hochstetter (1888). It would seem, how- 

 ever, from pathological conditions that such a normal connection 

 was at least suspected; see Serres (1830), Burow (1838), Russell 

 (1873), Sperino (1879), Brigidi (1888), Benique (1905-12). 

 An enlargement of such vessels was noted by Pegot (1833) and 

 Champneys (1872). 



Giacomini (1873) saw a connection between the portal and right 

 common iliac. 



VEN.E ILIACE 



The common iliac vein irregularities are largely associated with 

 the persistence of the left vena cava inferior already presented. 

 They occasionally receive an accessory renal vein or even the com- 

 plete renal drainage. They may be entirely separated from the 

 normally accompanying artery or may form a vena cometes al)Out 

 it, Quain (1844), Treadwell (1895). 



