KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 21. N:0 5. 



Syn. 1850. Clydonia gracilis, DANA. 



Tyro gracilis. 



— Proc. of the Amer. Acad. of Science and 



Arts. Vol. 2, p. 19. 

 » 1852. United States Exploring Expedition. Cru- 



stacea. Vol. 2, p. 834; pl. 55, fig. 6 



a— b. 

 Spence Bate. 1862. Catal. Araph. Crust. Brit. Museum, p. 284; 



pl. 47, fig. 8. 

 C. BovALLius. 1887. »Systeraatical list of the Ampliipoda Hy- 



periidea». Bih. t. K. Sv. Ak. Handl. 



Bd. 11. N:o 16, p. 4. 



As I have never scen any .specimen of this species the whole description is taken 

 almost literally from Dana, with some few additions, derived from my examination of 

 his drawing, 



The head is short, ahout half as long as wide, not keeled oii the upper side. 



The eyes consist of eight lenses round a central one. 



The jirst pair of antennce are stout at the base and gradually taper to an acute apex; 

 they have minute spines on the outer side and are short, pubescent on the inner. 



Along the sides of the segments of the pereion the oiitline of the epimerals is 

 barely distingnished. The la.st three pereional segments are as long as the first four. 



The first and second pairs of j)ereiopoda are short, hirsute, with small dactjdi. 

 The second pair are a little longer than the first. 



The third and fourth pair."^ are longer than the preceding, and very nearly naked. 



The jiftli pair are about twice as long as the fourth; the femur is about as long 

 as the next three joints together; the metacarpus is a fourth of the length of the femur; 

 the dactj^lus is verj- small. 



The sixth pair are much shorter than the fifth. 



The seventh pair are not half as long as the fifth. 



The first pleonal segment is a little longer than the second. 



The ural segments decrease rapidly in size. 



The uropoda are .slender, acute; the interiör coalesced ramus of the third pair is 

 almost as long as the peduncle. 



3. TYRO SARSI, C. BOVALLIUS, 1885. 



(Pl. I, fig. 1—17; Pl. II, fig. 1—10). 



Diagn. Coijms onrinattim. Capiif tertia parte altius qnam longiu.'?, .siiperne rarinatum, carinis diver- 

 gentibus. Antennce primi pari.s oorpore paullo breviores. Pede!< pereii primi paris carpis 

 ac dactylis elongatis. Pecle.s quinti ]>aris ])edibus sexti paris nnilto longiores; femur ante 

 leviter, post distincte serratum, articulis tribiis serjuentibus multo brevius, spinam rectam, 

 genu duplo lougiorem, gerens; tibia carpo multo brevior, carpus metacarpo ter fere longior. 



K. Vet. Akad. Handl. Band. 21. N:o 5. 



