CRUSTACEA. H 



4. HYASTENUS, White. 



Thorax suboblongus, ad latera rotundatus, ante et pone oculos directus ; parvo, transverso sulco in 

 superiore cantho. Frons duobus cornibus tlioraceni longitudine Bequantibus, primo parallelis, posterius 

 divergentibus et paululum deorsum directis ; antennis exterioribus omnibus articulis cylindricis ; inser- 

 tione articuli basalis cornu frontali occultatEi. 



Chela graciles, secundo pari pedum majori longitudine, graciUimo; articulo terminali acie spinosa. 



Carapace rather oblong, rounded on the sides behind, before and behind the edges 

 straight ; a slight transverse groove in the upper orbit ; front with two horns as long as the 

 carapace, at first parallel, and then diverging, and directed slightly downwards ; outer 

 antennae with all the joints cylindrical ; the insertion of the basal joint concealed by the 

 frontal horn. 



Fore-legs slender ; second pair of legs the longest, and very slender ; terminal joint with 

 the edge spined. 



A genus alhed to Hyas and Chorinus, the only species of which was long ago figured in 

 the large work of Seba. 



1. HYASTENUS SEB.E, White. 

 Superficie superiore subaspersa et pube velata. 

 Hab. Philippine Islands. 



Upper surface somewhat roughish, and covered with a delicate down. 

 Hab. Philippine Islands. 



Hyastenics Seba, White, List of sp. of Crust, in Brit. Museum ; Cancer araneus, cornutus alter, Seba 

 Thes. 3. 4. 5. t. 18. f. 12. 



5. CHORINUS, Leach. 



1. CHOEINUS ACANTHONOTUS, Adams $ White. Tab. I. Fig. 1. 



Tkorace quatuor longis spinis armato duabus anterioribus ad basin sese adpropinquantibus atque 

 paululum projectis, posterioribus bifidis ; furcis anterioris spinarum posteriorum lateraliter divergentibus, 

 posterioris longitudinaliter ; tribus spinis in utraque brachiali regione ; anteriore projecta, horizontaliter 

 depressa ; media gracili retrorsum, sursum et extrorsum projecta duobus acutis tuberculis ad basin deorsum 

 spectantibus ; posteriore duabus divaricantibus gracihbus spinis retrorsum et sursum directis. 



Rostro cornibus longis depressis, ad basin conjunctis, paulatim divergentibus et deorsum curvatis. Can- 

 thorum marginibus ad partem superiorem longa bifida spina armatis, ad anteriorem brevi bifida spina, et ad 

 posteriorem, brevi spina prorsum curvata finitis; canthorum margine inferiore fere obsoleto, angulo 

 externo in acuto dentali processu desinente. 



Chelis et supra et infra crista acuta denticulata armatis ; pedibus cylindricis, duobus spinis longis 

 prseacutis instructis, una in utroque latere superioris partis extremitatis articulorum disposita, sursum et 

 extrorsum tertiorum divergente. Tarsis longis curvatis, infra lsevibus. Corpore longis tenuibus setis co- 

 operto. 



Hab. Maria Orientaha ; Borneo (Unsang) . 



Carapace armed with four long spines, the two front ones rather close together at their 



