440 



spinules; propodal joint of the 2 anterior pairs rather elongated; the 3 

 posterior pairs rapidly increasing in length, and having the basal joint oval 

 in form and slightly serrated posteriorly, that of last pair, as usual, the 

 largest. Last pair of uropoda rather fully developed, reaching considerably 

 beyond the others, rami longer than the basal part, and edged with strong 

 spines, their opposite edges being, besides, very finely serrated, inner ramus 

 somewhat larger than the outer, and having its outer edge considerably 

 bulging out at the base. Telson oblong triangular in form, fully twice as 

 long as it is broad at the base, tip very minutely tridentate. Colour rather 

 variable, now light yellowish, with small specks of a dark brown or purplish 

 pigment, now variegated with large irregular patches of a very dark, nearly 

 black hue. Length of adult female generally not exceeding 6 mm. 



Remarks. This form was first described by Sp. Bate as a species 

 of Dexamine, and was subsequently referred by the same author to the genus 

 Atylus of Leach. It has, however, in reality very little affinity to either of 

 these genera, which, according to the author's opinion, do not even belong to 

 the present family. Boeck included the species in his genus Halirages, and 

 though it in fact bears a much closer affinity to that genus, I think it will 

 be more convenient to place it in the nearly- allied genus Aplierusa of Walker. 

 The Ampliitlioe macrocepliala of my late father and the ParampMthoe elegans 

 of Bruzelius are both undoubtedly identical with the present species. It may 

 be readily distinguished from the other species of this genus by the distinctly 

 prominent rostral projection, the large rounded eyes, and the peculiar shape 

 of the last pair of epimeral plates of metasome. Besides the usual littoral 

 form, is occasionally found another form or variety living in somewhat 

 greater depths. This variety grows to a somewhat larger size, and has the 

 eyes comparatively larger and less darkly pigmented, as also the body of a 

 lighter hue, but otherwise no essential difference is to be found between 

 the 2 forms. 



Occurrence. This species is very frequently found along the whole 

 south and west coasts of Norway, occurring, as a rule, in quite shallow 

 water among algee. According to Boeck, it extends northwards as far as 

 Troms0, Finmark, and Mr. Schneider has also found it occasionally in the 

 same tract. It is a very active little creature, swimming about with great 

 agility, the males especially being extremely rapid in their movements. 



Distribution. - British Isles (Sp. Bate), Bohuslan (Bruzelius), Kategat 

 (Meinert), coast of France (Chevreux), Mediterranean at Algeria (Chevreux) 

 and at Goletta (the author). 



