KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 22. N:0 7. 183 



»Body ovate, somewhat elongated at the tail, smooth, glossy, and when alive of an olive- 

 green minutely speckled with brown, but by drying becomes rufous-brown: antennas of the male 

 remarkably short; in the female two pairs extremely long, and slender, nearly equal to the 

 length of the body: joints of the body, independent of the head, and the joint to which the 

 caudal fins are attached, eleven; the head is large, and much resembles that of a maggot, and 

 in the male appears to have no division between the eyes, but a continuation of the same trans- 

 parent membrane covers the whole: the eyes of the female are very large, but distinctly marked 

 by a division: the two pairs of anterior legs, like those of C. spinosus, are small, and not sub- 

 cheliferous, but occupy the place of arms, and scarcely differing in any respect from the other 

 five pairs, all of which are furnished with a very small claw: abdominal fins three pairs; caudal 

 fins five, flat, and bifid; the middle one very broad, concealing the others which are capable of 

 spreading laterally. Length half an inch or more. 



The female is rather more slender in the body, and does not so suddenly decrease to- 

 wards the tail: the eyes, as before mentioned, are distinct, and are of a bright red when alive, 

 reticulated and marked with two streaks of black, one each side the eye, probably the reflection 

 of a pupil.» 



It must be observed here that Montagu mistook the sexes and called the male 

 female and the female male, but more remarkable is the fact that he expressely claimed 

 the difference in length of the antenna? as only a sexual characteristic, and it is to be 

 regretted that subsequent authors did not study his description enough to avoid the 

 mistake of making two separate genera of the two sexes. The value of Montagu's de- 

 scription as to the specific distinction of the animal in question is not ver}^ high, and it 

 would have been almost impossible to identify his species if we had not the statements 

 of White and Spence Bate, that his very specimens were preserved in the collection of 

 the British Museum. 



The tracing of the history of the species has, however, not been easy because Spence 

 Bate when he drew up his description of Hyperia galba in his »Catalogue» of 1862, 

 without further examination took H. galba and H. Latreillei to be synonymous, and 

 used a specimen of the latter species as the type for his description (see above p. 168). 

 When he and Westwood in 1868 gave a new description and drawing of H. galba, 

 they had for a type a specimen of the same species which Spence Bate in 1862 called 

 H. medusarum, and which I suppose to be the true H. galba. My reasons for this 

 supposition are not very strong and only negative for I cannot find any other Northern 

 species, which is provided with the broad femora given by Montagu in the drawing 

 reproduced above (p. 180). Under these circumstances it would probably have been more 

 strictly correct to drop the old name given by Montagu in favour of a new, but, as no 

 other species is known which can claim the name with better right than this, I have 

 preferred to retain it. Hyperia galba seems also to have been accepted by Th. Edward 

 and Norman within about the same limits as I give below. 



From Spence Bate's description of Hyperia medusarum in 1862 I quote the 



following lines: 



»First pair of gnathopoda short and robust, having the meros inferiorly produced and 

 tipped anteriorly with a few stiff hairs: carpus long, broad, and widening anteriorly, being in- 

 feriorly (but. not anteriorly) produced along the inferior margin of the propodos; anterior margin 

 fringed with a few stiff hairs: propodos not more than half the length of the carpus; superior 

 margin slightly arcuate, and fringed with four or five equidistant hairs; inferior margin straight, 

 armed with several small denticles: dactylos about half the length of the propodos, slender and 

 sharp. Second pair of gnathopoda having the meros inferiorly produced and tipped with a few 



