ORCHESXID^. < 



entire leg is shorter than the two posterior, which are subcqiml. 

 The coxae of the fifth and sixth are small. 



The two antepenultimate pairs of plcopoda are, in form, com- 

 mon to the genus ; the posterior is reduced in T. Locusta to almost 

 a ruchmentary stage, terminating in a solitary branch ; in fact, the 

 animal appears, ^nthout close insj^ection, to have but two pairs only. 

 The telson is absent or obsolete. We believe that this must be pe- 

 cuhai" to this species. 



The alimentaiy canal debouches in the position of the telson, on 

 either side of ^\-hich a few spines are situated, fixed upon a calcareous 

 base — the rudiments of the obsolete telson. 



The hairs or spines which arc appended to the legs and other 

 portions of the body are of a similar form over the whole animal, 

 with the exception of a few on the oral appendages. Although 

 constructed upon the same type in many of this family, yet their 

 exact form is capable of identification in this species. They are 

 short, stout, and strong, tenninating in a round, blunt extremity , 

 A\'ith a second appendage of similar appearance considerably smaller 

 originating not far from the point. They both assume traces of a 

 spiral character towards the apex. 



The microscopic structure of the integument exhibits traces of the 

 original cell-development and the granular arrangement of the salts 

 within the tissue, — besides which there are certain markings, peculiar 

 to the species, of a ~]~-shape ; these do not appear to be pores, and 

 have no apparent connexion wdth any peculiar function. 



The last three articidations of the pleon, Avith their styliform 

 appendages, complete the animal. The pleon lies inflected beneath 

 the pereion, from whence being forcibly expanded, it becomes a 

 powerful lever. By this means the animals can spi-ing to a con- 

 siderable distance, — a mode of progression of much value to them, 

 since they are inhabitants of chy land. 



The Talitri dwell upon sandy shores near the level of spring-tide 

 high-water mark, beneath old sea-weed or any rubbish that prevents 

 the too speedy evaporation of moistm-e. " In the fermenting and 

 half-rotten beds of Algae (chiefly Laminaria) at or above ordinary 

 high-tide level," writes Mr. Gosse to me, " I used to find the Crustacea, 

 at the depth of several inches in these heaps, along with dipterous 

 larvae, where it was so hot ^vith fermentation that I could scarcely 

 bear my hand in it." 



In the absence of such protection they generally burrow beneath 

 the sand to a depth of about three inches, more or less, according to 

 the dryness of the surface. Above their abodes may frequently be 

 observed small roimd perforations in the sand, which form the 

 entrance to their homes. From these places of concealment they 

 come out to feed under the rejectamenta of the sea, but skip to 

 their holes at the approach of danger. Say also observes of Or- 

 chestia Gnjlhis, that " when alaiTned it will seize a portion of its 

 food and skip with it towards its hole in the sand." 



Col. Montagu noticed that they retire in the coldest weather of 

 winter to a place of hybernation, or rather, perhaps, a position which 



