REPORT ON THE AMPHIPODA. 519 



when disturbed." He refers to the method, mentioBed by Sp. Bate, adopted by species of 

 Amphithoe of wrapping themselves about with sea-weed. This he observed in the case of 

 Amphithoe xienidJlata, Costa, and also in Heller's two species of Podocerus, which he names 

 Amphithoe lonr/ieornis and Amphithoe largiviana. (See Note on Kossmann, 1880.) The 

 Corophiinje adopt a third mode of using their secretion, in lining the walls of the channels 

 which they burrow in the mud. 



The second section treats of the unicellular glands in the genus Orehestia. Here the gland-cells 

 are distributed in different places over the whole body, but principally " in the coxal-plates 

 and the analogously formed lamellar expansions which are found on the bases of the three 

 hinder perteopods of both sexes and on that of the second pair of gnathopods of the female." 

 Small groups are found in the other joints of the legs, and in small numbers the cells are 

 found in the antennaj, mandibles, maxillipeds, last uropods, and elsewhere ; in the last pleon- 

 segment they form a large dorsal complex, reaching into the telson. The outlets are not as 

 in the Corophiidre by numerous tubes of various lengths, often uniting into a bundle before 

 reaching the common exit, but by short courses to independent pores opening in the 

 chitinous walls of various parts of the body. They are found in both sexes of Orehestia, of 

 terrestrial habit, but in Nlcea, more attached to the water, they are wanting, and may hence 

 have the function of preventing too rapid exhalation of moisture. 



Comparing his own observations with those of others, Nebeski concludes "that in the 

 Phronimids: and CapreUidx three to five or more gland-cells are united in the forn'.ation 

 of a secretory element and from this proceeds a cuticular emission-duct, while in the 

 Crevettina this formation of a complex does not occur, inasmuch as the secretory element 

 coincides with the histological, that is with the cell, and so a special cuticular passage 

 belongs to each cell. The Htjperidx seem to possess both types of glands, so that in this 

 respect they occupy an intermediate position ; at least Paul Mayer mentions that in these 

 Amphipoda ' in opposition to the Phronimidie the complex-formation only occurs in a 

 limited degree or is entirely wanting,' which would consequently betoken a nearer approach 

 to the Crevettina." 



The section on the renal glands attached to the intestine of the Crevettina is of considerable interest. 

 Nebeski cannot confirm Spence Bate's view that in Gammarus and Mxra there is but one 

 gland-tube, at least he himself always found two in Gammarus marinus and Gammarus 

 locusta as well as in Alsera hrevicaudata, and with this the statements of Wrzes^niowski 

 on Gammarus pmlex agree, although in Goplana polonica the right gland suffers 

 degradation in course of development. In Melita Nebeski found the gland unpaired. 

 In all the Corophiidse, ho says, we have two small tubular or vesicular structures 

 which rise obliquely li'om the intestine. Among the Gammaridas they are small 

 in Mxra, but in most they stretch in adult specimens through more than three 

 segments. For these the peculiarity is characteristic, that at their origin they bend 

 forwards, and, lying close to the intestine, run forwards more or less far. In Cyrtophium 

 they pass backwards through the long fourth, to the beginning of the fifth, pleon- 

 segment. In Nicea to begin with they turn backwards, but again bend forwards and end 

 just over the place of origin. In Orehestia they difi"er both in size and position. While in 

 all other forms, where the rectum quite uniformly occupies the tliree last pleon-segnicnts, 

 the tubes are placed on the intestine at the boundary between the third and fourth pleon- 

 segments, in Orehestia they arise in the seventh perajon-segment at the sides of the 

 intestinal canal, and with gradual elevation run backwards ; between the third and fourth 

 pleon-segments they lie dorsally on the intestine and here form the same flexure which 

 Nieea exhibits. The difference between Nicea and Orehestia is shown to depend on the 

 modification which the rectum has undergone in Orehestia. That the glands belong to the 

 mid-gut is a point on which Nebeski is in agreement with Mayer, 1882, and Baldwin 



