4 DR. HJALMAR BROCH [1918 



_ 



mantle, and helleves to have found degenerating ova at the upper 

 side of the ovaries, and in the basal parts of the mantle. 



It was thus obvious that al so at present anatomical questions 

 eoncerning Anelasma squalicola had to be answered, if we wish to 

 settle its po sit ion among the other cirripeds. At my request, Dr. O. 

 Nordgaard, the director of the biological station at Trondhjem, 

 procured material of the speeies, and I wish here to express my 

 sincere thanks for his valuable assistance. When we consider that 

 at most se ven per cent of the Eimopferus-specimens of the fjord are 

 inf ested with die parasite, it is easily understood that I never should 

 have succeeded in a abort time in getting so large a quantity of 

 material as needed, had I not been aided bj r the biological station. 



The investigations soon revealed the impossibility of settling 

 many questions from the litterature alone, without comparision with 

 other pedunculata. During our fjord investigations I had 

 ample opportunity of obtaining material of Scalpellum Strømii M. 

 Sårs, and my investigations have then naturally been extended to 

 a comparative study of Anelasma and Scalpellum. Owing to the 

 very scanty material of developing stages and simall specimens of 

 Anelasma I have at present confined myself to a study of the adult 

 ones, and, moreover, chie fly laid stress on elucidating the alimentary 

 organs and the cementary glands, which latter were hitherto 

 unknown in Anelasma. 



The study of histological details requires other methods of 

 fixation than those commonly used on expeditions where material 

 is gathered for systematical and geographical purposes. Even 

 though a fixation in formaline may isuffioe for many purposes also 

 in anatomical respects, it is soon found that in studies such as the 

 present, it is necessary to have recourse to other fixing solutions. 

 The best results I have obtained with Bouins solution (3 parts 

 concentrated hydrous picric acid, 1 part formaline -f- 3 — 5 % acetic 

 acid), and with Rabls solution (equal parts of concentrated 

 hydrous solutions of picric acid, and sublimate -\- 2 — 5 % acetic 

 acid). 



The microtome sections have been stained in different ways. 

 Good results for general purpose were obtained with Delafield's 

 haematoxyline — van Giesson. For finer details, the foilowing 

 staining methods were especially useful: Weigebts haematoxyline 

 — iron ammonium sulfate, Bøhmers haematoxyline — eosine, and 

 boraxcarmine — bleu de Lyon. A special interest is attached to the 

 latter double staining; bleu de Lyon shows special affinity to the 

 chitinogene parts, which attain a clear blue colour, and thus serves 

 to distinguish the chitinogene cuticle of the stomodæum and proc- 

 todæum from the covering layer of the digestive intestine. 



