THE CRAWFISH 195 



The exopocl, or ' ecphysis,' or ' palp,' is present, but as 

 cle Haan's figure shows, and as his statement declares, the 

 lash-like termination is absent. 



It rather looks as if Dana had stolen the type species 

 of ScyllcuruS) on which to found his new genus. At any 

 rate he changed Scyllarus arctus into Arctus ursus, both in 

 the generic and specific name making allusion to a bear, 

 not because of any resemblance in shape between Bruin 

 and this crustacean, but evidently because of the thick and 

 short pilose substance which protects the tuberculate sur- 

 face of the latter, and which is said to give it in its perfect 

 condition a smooth velvety appearance, like the shining 

 coat of the bear. 



Arctus ursus occasionally makes its appearance in Eng- 

 lish waters. It is recorded from many parts of the Medi- 

 terranean, and also from Australia and Japan. There are 

 several other species of the genus. They do not seem to 

 attain any remarkable size. 



Family 2. Palinuridce. 



The carapace is longitudinally subcylindrical, with 

 orbits for the eyes partially excavated. The second an- 

 tennae are subcylindrical, with a long rigid multiarticulate 

 flagellum, 



Spence Bate assigns to this family five genera, one of 

 which is found in British waters. 



Palinurus, Fabricius, 1797, is restricted by Spence Bate 

 to those species which have a small central rostriform tooth 

 or tubercle that overhangs but does not cover or enclose 

 the ocular segment, which have short flagella to the first 

 antennae, and in which the segment that carries those 

 antenna? is anteriorly produced and laterally compressed in 

 front. Such species appear to be confined to the northern 

 hemisphere. The type, Palinurus vulrjaris, Latreille, of 

 which the true specific name is involved in some perplexity, 

 is found in many parts of Europe, including the shores of 

 Great Britain. Bell considers that it is without doubt the 

 Carabos of Aristotle. It is a very handsome species, some- 



o 2 



