new remarkable Crustacean. ?,o\ 



oflif'v. This basis for classification was arlopted by Leach in 

 1815, and is to-day the generally accepted one. 



For some years ))ast, however, some few carcinologists, 

 notably Prof. Boas, and later Dr. H. J. Hansen, have con- 

 ceived that in certain circumstances this is not a natural 

 classification, and that in the more primitive forms of each 

 division — viz. the stalk-eyed Schizopoda and the sessile-eyed 

 Isopoda — some of the former are more closely related to the 

 latter than are some Schizopod families to each other. 

 Hansen differs in many points from Boas, and no subsequent 

 writer seems to have adopted their recommendations until 

 recently, when Di'. W. T. Caiman * has confoimed to 

 Hansen's suggestion (with some modifications and additions), 

 and done away with the Schizopoda as a natural group, 

 uniting some, the Euphausiacea, to the Decapoda fcrayfish, 

 crabs, &c.), and the remainder, the Mysidacea, to a large 

 group including all the sessile-eyed forms (Isopoda and 

 Amphipoda). 



'J'his is not the place to enter into a detailed discussion as 

 to the systematic position of the present species, but I shall 

 do so in another place, and give a detailed description, with 

 illustrations of its anatomy. SuflScient to say here tliat it 

 cannot be placed in Caiman's division Syncarida, composed 

 of the single order Anaspidacea, to which tiie present species 

 is rather closely allied, without considerable alteration of his 

 diagnosis; for instance, it has not all the thoracic somites 

 distinct, the anterior one being coalesced with the head, the 

 eyes are not pedunculated, nor are the thoracic limbs flexed 

 between the fifth and sixth joints, but between the fourth and 

 fifth. I can, however, respect his order Anaspidacea, so far 

 undefined, and in consequence of the present species I oft'er a 

 diagnosis of it. 



Should the opinion preponderate that the Schizopoda, with 

 the Euj)hausid and Mysid types both included, be kept for 

 the present as a natural group, then Anaspidacea may be 

 included as a tribe of that group. 



I am aware in joining the present species to Anaspidacea 

 that it originates an order possessing both stalked and sessile- 

 eyed forms, but J feel confident tliat the close relationshii) 

 shown in other respects of this new species to Anaspules 

 warrants such a union. 



Fundamentally the present species has the well-known 

 Schizopod characters, and, of the two rather widely divergent 



* "On the Classiliciitit)n of the Criu^tnroa Arahicostrncn," hy W. T 

 Calmfti), D.Sc. : Ann. ^: Mag. Nat. Hist. (7) xiii. p. 1 II (1904). 



