KiN r \i;i: si\()(isi!i:i;(; 



bristles. Thi' s c v i- it t li linih l\as ninrc {]\au twelve bristles. In .iililitiini this species dilTers 

 fn)in i>ther known forms of this genus in being tiuite witliout lati'iiil eyes. 



Of tln)se species tliat I have had no opportunity of investigating myself A. incri)iis, 

 (i. W . MlM.l.KH. 1906 b, seems to be very elosely related to this grou]). 



For the relation to this group of the following species that have iidt liecn investigated 

 bv me see the remark on A. Urimaldi: Ci/pridina Maricu', W. ]i\\\i\>, IH.'iO e, < '. oldoinjit. V). (JhUHI-J, 

 lsry\^.V!/liiidroh'bcii'< Marwe, (4. S. BRADY. 1868 b, Asterope oblonga, G. O. Sai{S, 1887, CyUndroleberis 

 ohhuga. (I. W. MCLl.liH. 1894, Asterope Mariae, G. S. Bkauv and A. M. Nohman, 1896, Cylimlro- 

 leberis Mariae, J. A. Cl sumax, 1906, C. Mariae, Cll. Jl'DAY, 1907, C.oblonga,}{. W. SllAHl'K, 1909. 



The only species among those described below that has not been mentioned so far, A. aberrala, 

 occupies a somewhat isolated position. It seems to be most closely related to%the Miilleri group. 



The characters in which it differs from this grouj) are as follows: — 



The elliptical shape of the shell. 



First antenna: — The marked reduction of the third and fourth joints. 



Mandible: — Second pro topodite j oint : Tlie backward pointing process: Tlie triaena brist- 

 les have from five to eleven secondary spines proximally of the distal pair of spines. Two dwarf 

 bristles are developed on this process. At the middle ofthe dorsal side ofthisjoint there is one bristle. 



The sixth 1 i in b, unlike that of other known forms, has no posterior ventral bristles. 



The seventh limb lias less than twelve bristles. The teeth of the end combs 

 are finely and uniformly pectinated. 



A. elliptica. G. 0. S.YHS, 1887 is probably ratiier closely related to this form. As to the 

 position of A. eUiptica, A. Philippi, 1840 see below p. 509. 



With regard to the systematic position of those of the species not investigated by me 

 that have not so far been mentioned I shall not try to put forward any opinion, as, on account 

 of the incompleteness of the descriptions, this would be so uncertain that its scientific value 

 would be exceedingly small. 

 Which species are the \Miich of the species SO far known are to be considered the most primitive? 



At the present moment this question can scarcely be discussed. It can only be said that 

 in one respect — the development of the d-bristle on the first antenna — the Quinquesetae 

 group is more primitive than the others. Whether it is also to be considered as more primi- 

 tive in other characters cannot be decided with any certainty, though it does not seem to me 

 to be impossible. 

 The type species oj The first specics of this gcnus to be described was A. elliptica, A. PHIUPIM, 1840. As this 



form — as is shown by the historical sketch, p. 433 — must be said to be unidentifiable as a 

 species, it can scarcely be convenient to consider it as a type species for this genus. I suggest 

 instead as the type species A. eUiptica, G. 0. SaRS, 1887, a species of which, it is true, we cannot 

 say with absolute certainty that it is identical with the form described by Philippi, but which 

 is, however, presumably very closely related to it. (G. W. MUIXEH makes this identification, 1912. 

 p. 46, but adds a query.) The form described by G. 0. Sars certainly needs to be re-described, 

 but it must be denoted as one that is identifiable as to its species. It may be noted that the 

 type-specimen of this form — according to a written communication to ine from Professor 



most primitive? 



this sennas. 



