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In establishing this genus in 1798 Fabricius divided it into 

 two sections, the first having the ocular spines simple, the 

 second having those spines dentate beneath. In the second 

 section he placed only the species Palimirus quadricorms, a 

 new name for what he and Herbst had previously called 

 Asiacus elephas. This has since been adopted as the type of 

 the genus under the name Palinurus vulgaris^ Latreille, 

 which ought perhaps rather to be called Palinurus elefhas. 

 Pennant in 1777 called this species Astacus homarus, con- 

 founding it with the Asiatic Cancer Homarus of Linnaeus. 



In 1884* T. J. Parker also divided the genus into two 

 sections, containing numerous species, distributed over three 

 sub-genera. The first of these sections, the " Silentes," 

 contained the sub-genus Jasus, and was defined as having, 

 " stridulating organ absent ; rostrum well developed, clasped 

 by paired pedate processes of the epimeral plates ; 

 procephalic processes present ; coxocerites imperfectly fused ; 

 antennulary flagella short." The species included lalandn, 

 Milne-Edwards ; edwardsii, Hutton ; hugelii^ Heller. Of 

 these Ortmann considers that edwardsii is a synonym of 

 lalandii. Jasus lalandii, though its specific name was given 

 by Lamarck, appears to have been first described by Milne- 

 Edwards. Dr. Gilchrist informs me that this species is 

 common at the Cape, grows to a large size, and is 

 commercially valuable. 



The second of Parker's sections was designated 

 " Stridentes," and distinguished as having " stridulating 

 organ present ; rostrum variable, but rarely (? never) as well 

 developed as in A [Section of the Silentes] ; pedate clasping 

 processes absent ; procephalic processes absent." This 

 section was divided into two sub-sections, the first containing 

 the sub-genus Palinurus, and having " Antennulary sternum 

 narrow below and bases of antennae consequently approxi- 

 mated ; bases of antennules hidden, in a view from above, 

 partly by the antennulary sternum, partly by the antennae ; 

 coxocerites imperfectly fused ; antennulary flagella short." 

 The sub-genus contained " Palinurus vulgaris^ in which 

 the rostrum is reduced to a small spiniform tubercle, with the 

 ophthalmic segment uncovered, and Palinurus trigonus, de 

 Haan, in which the rostrum is well developed, covering the 

 ophthalmic segment. This latter species had, however, 

 already been made the type of Linuparis, White, 1847. 

 Parker's second sub-section was opposed to the first by 

 having " Antennulary sternum broad below, causing a wide 

 separation of bases of antennae ; bases of antennules visible 



* See also Nature, v. 29, p. 190, 1883. 



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