92 ZOOLOGISCHE MEDEDEELINGEN — DEEL VI. 



VIII. — ON THREE MACRUROUS DECAPOD CRUSTACEA, ONE 

 OF WHICH IS NEW TO SCIENCE. 



BY Dr. J. G. DE MAN, OF IERSEKE. (WITH TWO TEXTFIGURES). 



Scyllarus ardus (L.). 



I am sorry to say that the key to the indopacific species of the genus 

 Scyllarus Fabr., published by me at p. 68 of Part III of my work on 

 the Decapoda Macrura of the Siboga Expedition (J. G. de Man, Siboga 

 Exp., Monogr. 39a 2 , Eryonidae etc. 1916) is in part incorrect. The sec- 

 tion g t at p. 70 should henceforth be read as follows: 

 g x Abdominal terga not at all prominent. 



h x Anterior extremity of the sternum with a deep triangular notch *). 

 i x Carapace with 2 teeth in the middle line before the cervical groove. 

 j\ First abdominal somite with a dark, oval spot in the middle. Cal- 

 cified portion of the telson terminating in four teeth. 



Both the inner and the outer margin of the proximal (outer) 

 antennal squame armed with only one well-developed acute tooth, 

 though one observes before the tooth of the inner and behind that 

 of the outer margin the trace of a second obtuse prominence. 

 Length, outer antennae included, 56 mm. . . sordidus (Stimps.). 

 j 2 First abdominal somite with no dark, oval spot in the middle. 

 Calcified portion of the telson terminating in two teeth. . pumilus JSTob. 

 (Gr. Nobili, Faune Carcinol. de la Mer Rouge, Décapodes et 

 Stomatopodes, 1906, p. 87). 

 i 2 Carapace with 3 acute teeth in the middle line before the cervical 

 groove. 



Outer margin of the proximal (outer) antennal squame with 

 two acute, well-developed teeth, though between the anterior tooth 

 and the apex the margin shows sometimes traces of 3, 4 or 5 

 minute obtuse prominences; of the five teeth on the inner margin 

 the second is the largest and the difference between this tooth and 

 the others is not so great as in Scyll. bicusjndatus (de Man). 



Length 125 mm., outer antennae included ardus (L.). 



h 2 Notch at the anterior extremity of the sternum not deep and 

 triangular, but presenting only a minute incision in the middle of 

 the truncate, posterior margin. 



1) In very young specimens of Scyll. ardus (L.), that are 34 mm. long, the outer antennae 

 included, the anterior extremity of the sternum still resembles that of Scyll. Ucuspidatus (de Man). 



