RECENT LITERATURE OF BLOOD-VESSELS. 375 



cells and cell-processes into flattened cellular elements is usually a subsequent 

 process. 



The mode of extension of the vascular system in growing parts of older animals, 

 as well as in morbid new formations, is quite similar to that here described, except 

 that blood-corpuscles are not developed within the cells which are forming the 

 blood-vessels. 



The blood-vessels may be said to increase in size and capacity in proportion to the demands 

 made on their service. Thus, as the uterus enlarges in pregnancy, its vessels become 

 enlarged, and when the main artery of a limb is tied, or otherwise permanently obstructed, 

 collateral branches, originally small and insignificant, augment greatly in size, to afford 

 passage to the increased share of blood which they are required to transmit, and by this adap- 

 tation of them to the exigency, the circulation is restored. In such cases, an increase takes 

 place in length, as well as in diameter, and accordingly the vessels very commonly become 

 tortuous. 



RECENT LITERATURE OP BLOOD-VESSELS. 



Epstein, S., Ueber die Structur normaler und elctalischer Venen, Virchow's Archiv, Bd. 108, 

 1887. 1 



Flemming 1 , W. , Ueber die Theilung der Pigmentzellen itnd Capittarwandzellen, Arch. f. mikr. 

 Auat., xxxv., 1890. 



G-eberg:, A., Ueber directe Anastomosen zivischen Arterien und Venen in der Nierenkapsel, 

 Internal. Monatsschr. f. Anatom. u. Histolog., ii. , 1885. 



Jones, C. Hand.fi.eld, Note concerning the endothelium of the small cerebral arteries, Journal of 

 Anat. and Phys., vol. xxi., 1887. 



Koeppe, H. , Muskeln it. Klappen in den Wurzeln der Pfortader, Arch. f. Anat. u. Physiol., 

 Physiol. Abth., Suppl. Band, 1890. 



Kolliker, A. v. , Histologische Studien an Batrachierlarven, Zeitschr. f. wissensch. Zoologie, 

 Bd. xliii., 1886. 



Mayer, S. , Studien zur Histologie und Physiologic des Blutgefdsssystems, Sitzungsber. der Wiener 

 Akad., Bd. 93, iii. Abth., 1886. 



Morpurgo, B., Ueber die Entwicklung der Arterienwand, Sitzungsber. d. Wiener Akademie, Bd. 

 90, iii. Abth., 1884. 



Plotnikow, V., Untersuchungen iiber die Vasa vasorum, Dissert., Dorpat, 1884. 



Relterer et Robin, Cb.., Sur la distribution des fibres elastiques dans les parois arterieUes et 

 veineuses, Journal de 1'anat., etc., 1884. 



Spalteholz, "W., Die Vtrtheilung der Blutgefdsse im Muskel, Abhandl. d. math.-phys. Kl. d. 

 Sachs. Gesellsch. d. Wissensch., Bd. xiv., 1888. 



Westphalen, W., Histologische Untersuchungen iiber den Bau einiger Arterien, Dissert., Dorpat, 

 1886 ; Ueber die Intima der Arteria uterina, Virchow's Archiv, Bd. 106, 1886. 



1 Epstein's paper may especially be consulted for many details regarding the differences of structure 

 of different veins, as well as for references to the older literature of this subject. 



