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elevated part, which as already mentioned sends forward a 

 long projection. 



The furrows which separate the urogastric lobe in front 

 from the metagastric lobe, and at the back from the cardiac 

 region, are curved, (with the concavity towards the front) broad 

 and flat, but yet distinct. The urogastric lobe is formed like 

 a flat, curved, rather narrow elevation. 



The epicardiac lobe is rather large, slightly heart-shaped. 

 In the casts indistinct traces of a few nodes are sometimes 

 seen on its front part. 



The metacardiac lobe is narrower than the epicardiac lobe, 

 and there is no distinct partition between the two. In the casts 

 traces of a small node on its front part are often seen. In 

 specimens with shell preserved I have not seen this node, nor 

 have I seen the two nodes on the epicardiac lobe. 



The orbital region is narrow, and rather long; the inner 

 part of its outer margin (the supraorbital margin) is thickened. 

 It is separated from the protogastric region, and the hepatic 

 region by flat, but distinct furrows. 



The hepatic region is rather large and bordered at the 

 back by the cervical furrow. Its highest part is about at the 

 middle, and somewhat behind that. 



The epibranchial lobe is — especially in the casts — 

 distinctly separated from the hepatic region; its border towards 

 the mesobranchial lobe is less distinct. The fourth node of the 

 anterio-lateral margin belongs as above mentioned to the epi- 

 branchial lobe. 



The mesobranchial lobe is well developed. It forms a 

 long fairly arched wall which, towards the middle of the 

 carapace, bends strongly backwards; at the back it slopes more 

 steeply than in front, where it is bordered by a very flat furrow. 

 At the back it is not bordered by any furrow, but here gradu- 

 ally unites itself with the metabranchial lobe. The strong fifth 



