250 CARL BOVALLIUS, AMPHIPODA HyPERHDEA. 1. 2. HYPERIIDiE. 



Parntliemisto. 



is the same species that Kroeyer described as Hyperia ohlivia, and for this reason it is 

 recorded below under the name Parathemisto oblivia, Krokyer. In 1887 I gave a 

 diagnosis of the new species P. japonica, and in 1888 Stkbbing proposed the new spe- 

 cies P. pacifica. Lastly I below describe P. GoÉsi, n. sp. The Parathemisto compressa, 

 GoÉs, on the other hand, recorded by Boeck in 1872 and by me in 1887 is a true Euthe- 

 misto, as suggested H. J. Hansen in the same year. ^) 



Thus we have to mention here the following species: 

 Parathemisto oblivia, Kroeyer. P. Batei, n. n. 



P. gracilipes, A. Merle Norman. P. japonica, C. Bovallius. 



P. rubescens. Dana. P. pacifica, Th. Stebbing. 



P. trigona. Dana. P. Goesi, n. sp. 



The sexual difference within the genus is expressed only in the form of the an- 

 tenna?, and in the somewhat wider and longer pera?on of the female. 



They eight species are to be distinguished according to the following synop- 

 tical table: 



A. The perteon is longer than the pleon. 



a 1. The front side of the carpal process of the second pair of perajopoda is 

 more than half as long as the liind margin of tiie metacarpus. 

 aa 1. The body is dorsally carinated. 



aaa 1. The carpal process of the second pair of peraopoda is pro- 

 vided with a terminal spine. 

 aaaa 1. The carpus of the first pair of perteopoda is a little 



shorter than the metacarpus 1. P. oblivia. 



aaaa 2. The carpus of the first pair of perajopoda is longer 

 than the metacarpus. 

 aaaaii 1. The outer ramus of the last pair of 



uropoda is as long as the inner 3. P. japonica. 



aaaaa 2. The outer ramus of the last pair of uro- 

 poda is shorter than the inner 3. P. pacifica. 



aaa 2. The carpal process of the second pair of pera^opoda wants 



a terminal spine.. 4. P. trigona. 



aa 2. The body is not carinated. The carpal process of the second pair 

 of perajopoda is provided with a terminal spine. The outer ramus 



of the last pair of uropoda is shorter than the inner 5. P. Batei. 



a 2. The front side of the carpal process of the second pair of perEeopoda is 

 not half as long as the hind margin of the metacarpus. 

 aa 3. The peduncle of the last pair of uropoda is three times as long as 



the telson (J. P. gracilipes. 



aa 4. The peduncle of the last pair of uropoda is not twice as long as 



the telson 7. P. Goési. 



B. The perjeon is shorter than the pleon . 8. P. rubescens. 



>) H. J. Hansen. »Oversig-t över det vestlige Grenlands Faunn uf inalakostrake Havkrebsdyr». Vidensk. 

 Meddel. fra den NatuHiist. Förening i KJ0benhavn. 1887, p. 59. 



