1(W 



■|'\(il-: sK()(;si;i:i{('. 



ltrlnltoiisliii> ••/ (A> 

 famHifs. 



Philomedex a mn- 



iiffiiiig link beUi'erii 



Ci/pritiinn niiii 



Kainily 1. ('i/priiiiiiuldc 



II. h'lifitli I itKifitldi 



I s\il>-fainily ('i/pridininor. 

 I'liiloincilinuv 



III. S(irsi.ell,i<lav 

 \\. Asterofidae. 

 It is piobahlo. lutwovor. tliat thoiv is not coiuplctc (Vjuivalence betwoen these four 

 families; vet this seems to me to bo the division that best reproduces their mutual re- 

 lations. In this case it might be said as G. W. Mullki{ wrote about the systematic position ol 

 the genus Rntidermn: ,,Aber schlieRlich ist das etwas Geschmackssache . . . ." 



IIiTc it may be pointed (uit iliat all the above-mentioned groups, Cijpridinume, 

 I'hi/omedinae. Rutidermatidae, Sarsi^llidnc and Asferojmlae are certainU- to be considered 

 ((uite natural. 



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. For the 

 present I shall therefore confine myself to merely a passing reference to it. 



The only writer so far who lias dealt .with the mutual relationship of the forms belonging 

 to these families is G. W. MOllicr. In his work of 1890 this author suggested on j). 224 that 

 the genus Philomedefi would form a connecting link between the genus Cypruima s. 1. 

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

 were 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 ihrem gesammten 

 A'erlauf als homolog bezeichnen miissen"; such ridges are, on the other hand, not 

 found in Cypridina. The selvage is smooth-edged in CypruUna, 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 com- 

 pletely or quite completely absent in Cypridina. 



With regard to the maxilla and the fifth limb the males of Philomedes would 

 form a kind of transitional type between Cypridina and Asterope. 



The sixth limb is jointed in Cypridiim 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 Schenkel der Zange sehr ungleich, 



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



The rod-shaped organ, like the upj^er lip, would be alike in Philomedes and Asterope; 



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



glandular fields. 



On the furca there sometimes appear secondary claws, ..Nebendornen" in Philo- 

 medes and Asterope; in the genus Cypridina there wo\ild ])e no such claws. 



