20 DR. HJALMAR BROCH [1918 



General results. 



In the preceding pages, a division of the alimentary canal into 

 four regions is generally adopted, which, however, does not 

 correspond with the four regions as defined by Gruvel (1905). 

 A comparison, indeed, shows that our interpretation and defmition 

 of the stomach is widely different. According to Gruvel, the 

 stomach means the foremost part of the digestive intestine where 

 the digestive glands open out. According to the definition here 

 adopted, the stomach means the hinder part of the stomodæal 

 region, where the muscles become scarce or disappear, the folding 

 of the wall extraordinarily rich, and the external shape of the 

 region accordingly rather ellipsoidal. The stomach as defined by 

 Gruvel is here included in the region of the digestive intestine. 



In a comparison of the alimentary canals of pedunculate 

 eir rip eds and crustacea de c ap od a the regions must 

 be parallelised in accordance with the definitions here adopted. In 

 the decapoda, the stomach as well as the oesophagus — i. e. the 

 entire stomodæal part of the alimientary canal — is lined with a 

 homjogeneous cuticle, which is the direct continuation of the exter- 

 nal thoracic cuticle. The digestive glands, on the other hand, 

 open into the middle part of the alimentary canal, the digestive 

 intestine proper; the latter is characterised by the striped end 

 parts of the epithelial cells («Ståbchensaum»), the striped cuticle. 

 Also in the E u p h a u s i i d s the same division holds good (comp. 

 Ra ab 1914); here again the stomach, both in its cardiacal, and 

 pylorical parts, is lined with a continuation of the thoracic cuticle, 

 and also in this group of crustaoeians the middle piart of the 

 alimentary canal, the digestive intestine, is characterized by its 

 digestive glands, and by its striped cuticle («Ståbchensaum»). In 

 the c i r r i p >e d s, the stomach is reduced to a simall subregion of the 

 stomodæal part, whereas the digestive intestine, on the other hand, 

 has attained a large size; the latter part is also here characterised 

 by its striped cuticle («Ståbchensaum»), and by its adjacent 

 digestive glands. Even though the digestive intestine in some 

 cirriped species is indistinctly subdiviided into two partitions, 

 nothing spieaks in favour of def ining the foremost partition as stom- 

 ach, the less so because the digestive glands in other crustaceans 

 open into the digestive intestine proper. 



A comparison of the alimentary canal in Anelasma squalicola 

 and the remaining c i r r i p e d i a pedunculata does not 

 reveal any quantitative reduction on account of the parasitic life of 

 the first nanied species. Quite on the oontrary, we must admit that 

 espeoially the digestive intestine is comparatively almost larger 

 than in Scalpellum, the organisation of Scalpellum Strømii agreeing 

 with that of the other Sealpelhim-species investigated by Hoek 



