.VO 'r\C,i; SKOOSHKRO 



lli'xur nf till' tittli joint. Tliis is very powi'iliil. and lias its inoxiinal at tacliiiiciit (loiso-proxiiually, 

 somowhiit latfrallv. in the fottrth joint and its distal attacliincnt at the vontral corner of the 

 fifth joint. — The female first antmna m this i^rcnus has a iiiusciilar system ol aliout the same 

 tvpe as that describeil lor the male, imt all the muscles ai'c very weak, and some ol them are 

 even (]nite absent. 



The de.seriptions given abo\ e will siiow that it is impo.ssible to lind l)et\V(M>n the niusenlar 

 svstein of tlie first antenna in the j^enns Euconclioecia on the t)ne hand and the <;enera Haloci/pris- 

 Conchoecia on the other agreements of sueh a nature as to permit of a quite certain homolog- 

 ization being carried out between the joints of tiiis antenna in these two groups. 



I cannot state anything very certain about the hoinologization of the joints of the first 

 antenna in the genus Archiconchoecia. — With regard to the numbers and positions of the bristles 

 this antenna .shows a considerably greater resemblance to Halocypris and Conchoecia than the 

 corresponding limb in the genus Euconchoecia does. Thus tiie second joint has a single bristle 

 dorsallv and the next to the distal joint has two bristles of about the same type as the bristles 

 on the corresponding joints in the genus Halocypris. The end joint has five bristles, i. e. the same 

 number as in the genus E^lconchoecia. Does this fact indicate that the bristles of this joint (and 

 the end joint itself?) are homologous in the genera Archiconchoecia and Euconchoecia, and that 

 the two sensorial filaments on the next to the distal joint on this limb in the former genus 

 (and in the genera Halocypris and Conchoecial) correspond to the great number of similar sens- 

 orial filaments on the next to the distal joint of the first antenna in the genus Euconchoecia^ 

 This does not seem to me impossible. The muscular system in this antenna in the genus Archi- 

 conchoecia is unknown; I cannot describe it myself owing to lack of material. It cannot there- 

 fore be produced here to help solve this problem. 



It is, of course, impossible at present to homologize the joints of the first antenna in this 

 sub-family with the joints on the corresponding limb in the other sub-orders. Neither the bristles 

 nor the muscular systems in any of the forms so far known in detail seem to afford any support 

 for a solution of this problem. A closer investigation of this antenna in the genus Thaumalo- 

 cypris would, however, be interesting as throwing light on this question. 

 y umber of joints on As is Seen above, I have established the presence of nine joints on the exopodite of this 



the exopodite of the ,j^^_ ^j^j^ number was alreadv given bv C Cl.\us, e. g. 1891 a, p. 22. G. W. MCller, 



second antenna. . o . -^ 



on the other hand, always gives only eight joints for this branch (cf. this writer, 1894, p. 37, 

 1906 a, p. 30). 

 The joints on the With regard to the appendage on the endopodite of this limb for seizing and holding 



endopodite of the j^^^ ^^^ female I have followed G. W. MUller; in other words this appendage has been explained 



second antenna. '- ^ " 



in the present work as the distal joint of the endopodite. — C. Glaus took another view of this 

 problem. According to him the distal part of the second joint (according to G. W. MOlleu's 

 explanation), i. e. the part that has the f- and g-bristles, corresponds to the end joint of the endo- 

 podite, and the clasping organ is an accessory appendage on the original second joint. Other 

 writers do not express any quite distinct opinion in this question, but they seem, as a rule, to 

 have inclined to C. Claus's view. — Both G. W. MUller and C. Claus take up a very decided 

 position in this question. The problem seems to me, however, exceedingly difficult to decide 



