CLASSIFICATION OF THE MAIOID CRrSTACEA. 



G39 



fossiles ' *, establishes two families, luacliouliens aud Maiens, 

 apparently corresponding to Dana's Maiiuea and Parthcnopinea. 



The late Dr. Stimpson, in his Preliminary Eeport of the Crus- 

 tacea Brachyura dredged in the G-ulf Stream t, points out several 

 errors in Dana's classification, and proposes or amends the cha- 

 racters of several subfamilies and families. Of these the Peri- 

 ceriutT, Othoniinrc, Eurypodiidfe and Acanthonychidoe would 

 seem to correspond respectively to my Periceridae, Othoninie, 

 Inachidse and Acanthonychina) ; but as often only a single 

 character is mentioned by which to distinguish the groups, and 

 no lists of the genera included are given, the limits he would 

 have assigned to them had he lived to publish a complete system 

 must remain uncertain. His subfamilies Leptopinse and Collodinae 

 are not retained in the present classification. 



It may be useful in conclusion to refer to the arrangement 

 adopted by Dr. Glaus in his lately-published Treatise on 

 Zoology (G-rundziige der Zoologiej 3te Aufl. p. 558, 1876), as, 

 although this author does not do more than indicate the 

 leading generic types of the Oxyrhyncha, his views are of spe- 

 cial interest as emanating from a carcinologist of the highest 

 reputation. In his system the Oxyrhyncha are divided into two 

 families — Majidae, Parthenopidie — corresponding to the first and 

 second of Dana's legions ; and the Majidae are further subdivided 

 into three subfamilies : — (1) Majinse, in which the eyes are retrac- 

 tile into orbits ; (2) Eurypodinae, in which the eyes are retractile 

 but without orbits ; and (3) Leptopodiinse, with non-retractile 

 eyes. 



In the present revision the first aud second of Dana's primary 

 groups (Maiiuea, Parthenopinea) are retained. The remarkable 

 genus Oncinopus, for which Dana established a section (Oncininea) 

 equal in value to the two above mentioned, must, I believe, be 

 included in my family Inachidae. The abbreviated character of 

 the basal antennal joint is not peculiar to it, but exists also in 

 Maeroclieira ; the genus, however, exhibits a certain degradation 

 from the Brachyura in its subdorsally raised fifth ambulatory 

 legs. In its antennal characters, no less than in the flattened 

 triangulate form of the carapace, it approaches the Grapsoid genus 

 Elamene and its allies. 



* Ann. Sci. jS'at. tome sir. Zjo\ p. 185 (1830). 

 t Bulletin of Museum of Comparative Zoology, ii. p. 109 (1870). 

 LT^N. JOTJEIf. — ZOOLOGY, YOL. XIY. 48 



