ON THE LAKE VILLAGE AT GLASTONBURY. 423 



50. Piece of cut wood, max. length 6^ inches ; average thickness 245 inches, 

 half-notched at middle-third, with peg through centre of notch. Found in the peat 

 under Mound 68. 



Botanical Specimena. 



From peat under Mound 67. — Corylus avellana (ha,zQi\n\i.t'); Fontinalis (,f[o2iimg 

 moss) ; Carex rijiaria ? (sedge). 



Mound 72, from bottom floor. — Pigvmgatiiirm (cultivated pea) ; Triticum sativum 

 (wheat) ; llordcum vuhjare (barley); Corylus avollana (hazelnut). 



Mound 72, from third.floor level, but a little to the W, of the mound.— Jrt* 

 jfsevdacorus (yellow flag), 



There are others not yet identified. 



The Ductless Glands. — Second Interim Iiej)ort of the Commiitee, con- 

 sisting of Professor Schafer (Chairman), Professor Swale Vin- 

 cent (Secretary), Professor A. B. Macallum, Dr. L. E. SHORE, 

 and Mr, J. Barckoft. (Drawn ^t2J by the Secret ary.) 



The Nattire of the 'Islets of Langerhans^ in the Pancreas. 



The majority of writers, especia]Iy among pathologists, look upon the 

 ' islets of Langerhans ' as constituting a tissue, sui generis, bearing little or 

 no relation (except perhaps a similarity of embryonic origin) to the zymo- 

 genous tubules of the gland. The present investigation tends to show 

 that this view, which has already been challenged by Dale, is not the 

 correct one. 



The ' islets ' are in all animals in direct continuity with the zymo- 

 genous tissue, and all kinds of transition forms are frequently to be met 

 with. In mammals it is often difficult to detect any line of demarcation 

 between tubules and islets, and this is even more difficult in birds, reptiles, 

 and lower vertebrates generally. 



In birds and reptiles a lumen can often be detected in the cell columns 

 of the islets. This applies also to some teleostean fishes. 



Moreover the intimate relation between zymogenous tissue and islets 

 is shown by the fact that it is possible to convert zymogenous tissue into 

 islet by exhaustion and inanition. In the latter case the islet tissue is 

 reconverted into zymogenous when the animal is restored to its normal 

 condition. This interchangeability has been noted in mammals, birds, 

 and amphibians. 



The study of the pancreas in birds and reptiles revealed the presence 

 of a third kind of tissue in the vertebrate pancreas which seems not to 

 have been previously described. This is most typically seen in the two 

 groups mentioned, though its presence has been verified in other groups 

 also. The tissue stains deeply with ordinary staining reagents, and there- 

 fore the name ' bathychrome ' is suggested for it, while in contrast we 

 may call the known ' islets of Langerhans ' ' leptochrome,' since these stain 

 less deeply than the surrounding zymogenous tissue. The nature of the 

 bathychrome tissue and its relations to the other constituents of the organ 

 are at present under investigation. 



A full account of the results so far obtained will be published in the 

 * Internat, Monatsschr. f. Anat. u, Physiol.' 



