Sludics on inuriiio Ostracod.s 167 



related to each other than to the sub-families SarsieUinae and Asterofinae; the similarity 

 between the two latter sub-families is, in addition, considerably less than that existing between 

 Cyfridininae and Philomedinae. 



With regard to the classificatory position of the genus Rutiderma the following infor- 

 mation, taken from G. W. MtlLLEH's work of 1908, p. 91, may be put forward. (I have 

 unfortunately had no opportunity myself of personally investigating any form belonging to this 

 interesting genus): 



The shell reminds one strongly of the shell of some species belonging to the sub-familv 

 Philomedinae, but on the other hand it undoubtedly approaches the type of shell in the 

 sub-family Sarsiellinae. 



The first antenna shows entirely the same structiu-e as that of the females of Sarsiella. 

 Second antenna: The reduction of the endopodite of this antenna reminds one of 

 Sarsiella; the bristles on the exopodite of the females of Philomedes. 



The mandible has a structure that differs greatly from all other s t r a c o d s. 

 but still it shows a certain relationship both to Philomedes and to Sarsiella. 



The maxilla shows a type rather similar to that of the females of Sarsiella; it 

 has, on the other hand, no close i-esemblance to Philomedes. 



The fifth limb is, on the contrary, considerably more like this appendage in 

 the sub-family Philomedinae, it has no close resemblance to this appendage of Sarsiella. 

 The sixth limb is about half way between Philomedes and Sarsiella. 

 The remaining organs ,,scheint bei der Beurteilung der Frage nach den verwandt- 

 sc^haftlichen Beziehungen kaum von Wert". 



Finally on the page just mentioned (i. W. Mf'M.Eli writes as follows: ,,Versuchen wir an 

 der Hand des gegebenen Materials die Frage nach der Zugehorigkeit zur einen oder anderen 

 UnterfamiUe zu beantworten, so scheint es nicht leicht, diese Antwort zu geben; mit beiden 

 Unterfamilien stimmt sie in Organen iiberein, deren Bau fiii' die Unterfamilie be.sonders charak- 

 teristisch, mit Philomedes ini Bau des ersten und zweiten Thoraxbeines, mit Sarsiella im Bau 

 der ersten Antn., der Mandibel und der Ma.ville, doch ist zu bemerken. dalJ sich die erste Antn. 

 auch nicht allzuweit von der von Philom^'des % cntfernt, und daB die (Hjereinstinunung mit 

 Sarsiella im Bau der Mandibel keineswegs eine vollstiindige ist. Im ganzen ist unzweifelhaft 

 die tlbereinstimmung mit den Philomedinae groBer, und halte ich es fiir angebracht, sie dieser 

 Unterfamilie einzureihen. A her schlieBlich ist das etwas Geschmacks.sache, da die verwandt- 

 schaftlichen Beziehungen zu beiden Familien imzweifeUiaft" .... 



This result, the grouping of the genus RiUiderma with Pliiloiiwdes and Pseudoph ilomedes 

 into one sub-family, seems to me incorrect. For even if Rutiderma were to turn out to agree 

 somewhat more closely with the two latter genera than with the sub-family Sarsiellinae, it 

 represents, all the same, a rather divergent type, it seems to me, therefore, more convenient 

 to follow the example of G. S. BRAD'S and A. ]\I. NoR^^.■\^■ and to distinguish this genus iis 

 a representative of a higher classificatory unit. 



The result of this discussion is consequently that neither of these two divisions is to be ac- 

 cepted unaltered. The following combination of the two has been used by me in the present work: 



