-1:32 THE VOYAGE OF H.M.S. CHALLENGER. 



synonym of Kroyei's species, and if he is correct in this our species is undouhtedly distinct " ; 

 Vertummi.i serratiis ?, Goes (Fabricius sp.), {Acanthonoius serratus, Stimpson), " Our 

 specimens all differ from the descriptions and figures given by Boeck and Kroyer in the 

 armature of the posterior margin of the third segment of the abdomen. In our specimens 

 the upper process from this margin is armed with four or five teeth above and at the tip, 

 while the lower process is armed with five or six teeth simOarly situated, but with no teeth 

 on the lower margin except just at the tip. In Kroyer's figure (Gronlands Amfipoder. 

 plate ii. figure 8) the upper process is represented as terminating in a single tooth and the 

 lower process as toothed along both sides; Boeck's description agrees with this, except that 

 he says there are two teeth at the tip of the upper process "; Boeck afterwards changed the 

 name to Acantlionotozoma senritum ; Acanthozone citsjddata, Boeck ; Byhlis gaimardi, 

 Boeck (Kroyer sp.), "the Ampelisca Gaimardi of Bate, and Bate and Westwood, is not this 

 species, but a true Ampelisca. All the species of this subfamily are undoubtedly tube 

 dwellers. ... In this species, the glands which secrete the cementing fluid are situated 

 principally in the meral and basal segments of the third and fourth pairs of thoracic legs ; " 

 Xenodea viegacidr. Smith, n. s., PI. IV [III], figures 1 to 4. " ' Pedes Stii et 4ti paris 

 articulo Imo latissimo ' of the generic description would scarcely apply to our species, but in 

 all the other generic characters it agrees perfectly, as it does also with the diagnosis of the 

 subfamily Photinae, except that the mandibles each bear six serrated spines instead of the 

 usual number, four." In this species Professor Smith noticed a peculiar " glandular structure 

 fiUing a large portion of the third and fourth pairs of thoracic legs." " The terminal seg- 

 ment (dactylus) in these legs is not acute and claw-like, but truncated at the tip and 

 apparently tubular." " A large cylindrical portion of the gland lies along each side of the 

 long basal segment, and these two portions uniting at the distal end pass through the ischial 

 and along the posterior side of the meral and carpal segments, and doubtless connect with 

 the tubular dactylus. There can be no doubt that these are the glands which secrete the 

 cement with which the tubes are built, and that these two pairs of legs are specialized for 

 that purpose." In AmjjMthoe maculata the gland is in the middle of the basal segment. 

 Other arrangements with reference to this gland are mentioned for Cerajms mhricorni)', 

 Ptllocheirus pincjuiif, Byhlis gaimardi, and a species of Anqxlisca. 



1874. Smith, S. I. 



Tube-huilding Amphipoda. The Annals and Magazine of Natural History. 

 No. 81. September 1874. Vol. XIV. Fourth Series. London, 1874. p. 240. 

 Silliman's American Journal, June, 1874. 



The cement-glands are described in Xenodea sp., and noted in Amphitho'e maculata, Pfiloclietrua 

 pinguis, Cerapus rubricornis, Byhlis gaimardi, Ampelisca sp. In the Cerapus " the 

 orifice in the dactylus is not at the very tip, but subterminal on the posterior side." In 

 Ampelisca and Eijhlis " the remarkable elongation of the two distal segments in the third 

 and fourth pairs of legs is perhaps a special adaptation to enable them to reach back over 

 the deep epimera." See Note on Smith and Harger, 1874. 



