Iiiniilii's. 



iici-lin^ link hcUvcrii 

 Ci/linihti'i iiinl 



lt;.s TAdio sK()(:si;i';i!(; 



.,■ , f suli-familv ( 'ypriflminae 

 Faiinlv I. Cypnatmdac. [ ' ,,, ,7. 



•" ( ., „ I liilotnedinae 



II. Rutulermatidar 

 ,, III. t>arsiellidae 

 W. Asteropnlae. 

 It is probable, liowever, that there is m)t coiiiplete equivalence between these four 

 laniilies; vet this seems to me to be the division that best reproduces their mutual re- 

 lations. In this case it might be said as G. W. MtJLLER wrote about the systematic position of 

 tlie genus Rutiderma: ,,Aber schlieBlich ist das etwas Geschmackssache . . . ." 



Here it may be pointed out that all the above-mentioned groups, Vyfridirmme. 

 Philnme-dinae, Rulidermatidae, Sarsiellidae and Aftteropidae are certainly to be considc'i'ed 

 (|uite natural. 

 itrhiiioiiship nf ihr Which Is the mutual relation of the above-mentioned four families? 



It still seems to be too early to try to enter more closely into this problem. Foi' the 

 pn^sent I shall therefore confine myself to merely a passing reference to it. 



The onlv writer so far who has dealt with the mutual relationshiji of the forms belonging 



to these families is (i. W. Mullkr. In his work of 1890 this author suggested on p. 224 that 



the genus PhilomedeH would form a ct)nnecting link between the genus Cypridina s. 1. 



and the genus Asterope. The reasons that seemed to this author to support this assumption 



I •<i('rn /;,■:' wove as follows: 



The shell: In the genera Philomedes and Asterope there sometimes appears 

 a sculpture of the shell in the form of prominent ridges ,,die wir nach ilu-em gesammten 

 Verlauf als homolog bezeichnen miissen"; such ridges are, on the other hand, not 

 found in Cypridina. The selvage is smooth-edged in Cypridina, in Philomedes it is 

 broken up into hairs at the margin, in Asterope it is quite broken up into hairs. 

 Mandible: The endite on the coxale is small and simple in Cypridina, somewhat 

 larger and bifurcated in Philomedes, large and very deeply bifurcated in Asterope. The 

 endite on the basale is large in Asterope, somewhat weaker in Philomedes, almost coin- 

 pletely or quite completely absent in Cypridina. 



With regard to the inaxilla and the fifth limb the males of Philomexl^es would 

 loiiu a kind of transitional type between (Cypridina and Asterope. 



The sixth limb is jointed in Cypridimi and in this genus the different joints are 

 moved by special muscles, in Philomedes this appendage is jointed, the different joints 

 would, however, not be moved by special muscles, in Asterope it is quite unjointed. 



Seventh limb: In the genus Cypridina ,,sind beide Hchenkel der Zange sehr ungleieh. 



bei Philomedes sind die Unterschiede geringer. bei Asterope sind sie fast ganz geschwunden". 



Tlie rod-shaped organ, like the upper lip, would l)e alike in Philomedes and Asterope; 



the upper lip in these two genera would be specially characterized bv the absence of 



glandular fields. 



Oil the furca there sometimes appear secondary claws, ,,Nebendorne.n" in PJiiht- 

 medes a?ul Asterope; in the genus (Cypridina there would be no such claws. 



