Sliidii's oil iiiiuiiio Ostracods 1()< 



related to each other than to the sub-families Sarsiellinae and Asteropinae; tlie 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. MUllek'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 sliell of some species belonging to the sub-family 

 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 structure 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 otlier 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 resemblance 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- 

 schaftlichen Beziehungen kaum von Wert". 



Finally on the page just mentioned G. W. MuiJ.EP. writes as follows: „Versuchen wir an 

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

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

 Unterfamilien stimmt sie in Organen iiberein, deren Bau fixr die Unterfamilie besonders charak- 

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

 der ersten Antn., der Mandibel und der Maxille, doch ist zu bemerken, daB sich die erste Antn. 

 auch nicht allzuweit von der von Philomedes 9 entfernt, und daB die t'bereinstimmung mit 

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

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

 Unterfamilie einzureihen. Aber schlieBlich ist das etwas Geschmackssache, da die verwandt- 

 schaftlichen Beziehungen zu beiden Familien unzweifelhaft" .... 



This result, the grouping of the genus Rutiderma with Philomedes and Pseudojjhilomedes 

 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-famih- Sarsiellinae, it 

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

 to follow the example of G. S. BRADY and A. M. NORMAN and to distinguish this genus as 

 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: 



