ICONGL. SV. VK'\\ AKADKMIKN.S IIANDMNGAK. HAND. 22. NIO 7. 307 



Euthemisto Itispinosa, A. BOECK. C. Bovali.ius. /<S'cS'7. "S^isteniatical list of the Ainplii- 



poda liyperiidea». Bih. t. K. 

 Sv. Vet. Ak. Harull. Bd. 11. 

 N:o IG, p. 22. 

 » » M » ]8S'7. »Arctic aud Aiitarotic Hyperids». 



Vega-Exp. Vetensk. Iakttagel- 

 ser. Bd. 4, p. 569, pl. 46, 

 fig. 97—103. 

 » w » Til. Stebbing. 188S. »Reporten the Araphipoda". Voy. 



of H. M. S. Challengei-. Zoo- 

 logy. Vol. 29, p. 1408. 

 1878. Lestriijomis spinidovsalis, SPENCE BATE. — uTwo iiew Crustacea from the 



coast of Aberdeen». Ann. and 

 Mag. of Nat. Hist. 5"^ Ser., 

 Vol. 3, p. 411, fig. 2. 

 Hijperia spinidorsalis, » — 1878. »On the Willemoesia Group of 



Crustaceau. Ann. and Mag. of 

 Nat. Hist. 5'*" Ser. Vol. .3, 

 p. 489. 



Aftei- having compared many individuals of both sexes and different ages of the 

 two SLipposed species Themisto compressa and Th. hispinosa, I am convinced that they 

 are one and the same species, as Hansen also suggested in 1888. The species naust 

 therefore have the older name given by GoÉs in 1865, and it is here recorded as Euthe- 

 misto compressa, GoÉs. 



The original diagnosis runs: 



T. compressa n., carinata segmentum septimum saspe etiam sextiim et octavum margine 

 postico in spinulam productum dorsalem in juvenibus exiguam, in adulto facile conspicuam; an- 

 tennas ef flagello multiarticulato, tenuissimo, valde elongato ut in Hyperiis omnino.» 



The drawings which accompany his description are however somewhat erroneous, 

 and suggest the idea that the fifth pair of perseopoda are built exactly as the sixth pair, 

 and are quite as long, the animal thus being a Parathemisto and not an Euthemisto; 

 but after examining his type-specimens, now preserved in the Natural History Museum 

 at Stockholm, I find that this is only due to a misconception of the draughtsman, as in 

 all the specimens labelled by GoÉs's hand, the carpus of the fifth pair is distinctly longer 

 and broader than in the sixth pair, and that in only one single specimen the fifth pair 

 do not reach distinctly beyond the apex of the sixth. 



A. BoECK in 1870 gave the following diagnosis of Parathemisto compressa: 



»Segmentum trunei ultimum et segmenta postabdominis duo anteriora carina spinas retro- 

 versas formanti. Pedes 3tii et 4ti paris articulo 4to magno, elongato-ovali. Pedes 5ti paris arti- 

 culo 4to duplo longiore qvam articulo 3tio.» 



And of Themisto bispinosa he gave the following diagnosis: 



»Corpus compressum, segmentum trunei 6tum et 7mum in medio margine posteriore in 

 spinas producta. Pedes 3tii et 4ti paris articulo 4to oblongo. Pedes trium parium ultimorum 



