On the Relations between tlie „Islets of Ldngerhans'' etc. 89 



Some among the first group even consider that there may be no 

 difference in function between the two structures. Thus Hariis and 

 Gow ^) thought that the islets might take part in the external secietion, 

 probably forming one of the ferments. Jarotzky"^) believes that they 

 may take part both in an internal and an external secretion. Lewa- 

 schew'^) and Pischinger'^) look upon the islets as exhausted secreting 

 cavities, and believe that after a period of repose they may again 

 take on their secretory function. 



Tschassownikow ^) and Dogiel^) on the contrary look upon the 

 islets as exhausted acini Avhich are unable to return to their former 

 state. It will be seen that the four last-named observers held a view 

 not widely differing from that of Laguesse, Dale, and ourselves. 



Statkewitsch ') looks upon islets as alveoli modified by inanition 

 and Manko wsky^) emphasises to the full the intimate relation sub- 

 sisting between islets and tubules, their functional variations and forms 

 of transition, but does not appear to have committed himself as to 

 their functions®). 



In most vertebrates, as we have seen in the preceding text, there 

 are no lumina in the Islets of Langerhans. But Gianelli and Gio- 

 comini^^) described lumina in the islets of reptiles and although Gianelli ^^) 

 seems later to have developed doubts on this point, yet their existence has 

 been fully confirmed by Laguesse ^^) and by Perdrigeat and Tribondeau^'^). 

 Laguesse has given very convincing illustrations of his results on this 



') Joiirn. of Physiol. Vol. 15, p. 349. 1894. 



2) Virch. Arch. Vol. 156, p. 409. 1899. 



3) Arch. f. mikr. Anat. 26. Bd. S. 453. 1886. 



■*) Beitr. z. „Kenntnis d. Pankreas"'. Inaug.-Diss. Munich. 1895. 



^) Ref. by Mankowski, Arch. f. mikr. Anat. Vol 59, p. 286. 1902. 



«) Arch. f. Anat. u. Physiol. S. 117. 1893. 



') Loo. cit. 



*) Arch. f. mikr. Anat. Bd. 59. 1901 ; Nachrichten der Kaiserl. Univ. Kiew. 

 1900. In Russian, 



®) Mankowsky's full paper, the contents of which we have gleaned from the 

 abstract in Arch. f. mikr. Anat., is beautifully illustrated. 

 ") Proc. verb. d. R. Accad. d. Fisiocrit. Siena 1896. 

 ") Loc. cit. 

 ^2) Loc. cit. 

 ^^) Procès-verbaux de la Société Linn, de Bordeaux, t. LV, séance du 24. Oct. 1900. 



