564 TAGE SKOGSBERG 



aufstclleii nuiliten. Man sielit, wir niihern uns dem Ideale iiiancher Systeniatiker, die 

 aiis jeder Art cine besondere Faniilie nuichen niochten." He then suggests tliat the 

 l'ainil\- Halocypridae should be divided directly intti lour genera: Conchoecia, Halocypris. 

 Eucnnchoecia and ArcJiiemichoecia. No grouping of the species within the genera was un<h'i- 

 taken in this work. 



(i. W. Mi'I.LEIi, in his monograph on the () s t r a c o d s of the V a I d i v i a expedition, 

 the most important work on the Haloci/priformes after 1894, described a new and very different 

 Haiocyprid genus, Thaumatocypris. and put it as the sole representative of a new sub-family. 

 Thaumatocyprinne, opposiMl to all the other H a 1 o c y p r i d s, which were grouped into one 

 suli-familv. CoticJioecinae. This last sub-family was divided by this writer into the same four 

 genera as in his Naples monograph, namely Arcliiconclioecia, Ha/ocypris, Conchoecia and EticmicJi- 

 oecia. The two first and the last of these four genera, which comprised a rather small number 

 of species, were not divided any further. A splitting-up of the multiform genus Conchoecia 

 (no less than 75 species of tliis genus are included in the work mentioned) was. on the other hand, 

 desirable even for practical reasons. G. W. MULLER writes on this in the work in question 

 (p. r)2): .,Auch gelingt es ja leicht, natiirliche Gruppen abzugrenzen und wenigstens einige dieser 

 (Jruppen scharf zu charakterisieren ((rruppe curta, rotundata, hispinosa), bei anderen Gruppen 

 gelingt entweder die scharfe Abgrenzung oder die Gharakterisierung der Gruppe nicht (spinifcra. 

 magna, mollis). Gewohnlich greift man in iihnlichen Fallen die leicht charakterisierbaren 

 (iruppen heraus, stellt sie als gleichwertige Gattungen der alteren. alle umfassenden Gattung 

 gegeniiber, in der man den undefinierbaren Rest belal3t, dessen Auflosung nicht gelingen will, 

 und der dann keine natiirliche Gruppe mehr darstellt, auch keine scharfe Charakteristik zuliiiit. 

 Man vergleiche z. B. das Scliicksal der Gattungen Ci/pris, Cythere und Cypridina. Auch der 

 Versuch von Glats. die ({attung Conchoecia aufzulosen, gehort bedingt hierher. Seine neuen. 

 meist nur durch eine Art vertretene Gattungen reprasentieren natiirliche Gruppen, die Gattung 

 Conchoecia umfal.5t Vertreter verschiedener Gruppen; doch wird hier wenigstens der Versuch 

 (rpmacht, auch diese Gattung; scharf zu charakterisieren. Ich halte ein solches Verfahren nicht 

 fiir streng wissenschaftlich, habe deshalb von einer Auflosung in Gattungen abgesehen." 

 In other words this author protests against a division into new genera of the genus Conch- 

 oecia. but puts forward the possibility of distinguishing natural groups; no less than sixteen 

 such groups were established in this work. But he pointed out at the same time that it was 

 perhaps possible that a careful study of the limbs to which no attention had been paid ,,schatl't 

 die Moglichkeit einer voUstandigen Auflosung in Gattungen''. 



This writer uses the same classification in his later works (1912), but does not divide 



the genus Conchoecia into groups. He was followed by some other writers, e. g. Gil. Ji day. 



19(»(i and T. R. R. Stehbinc, 1910. 



"'■■"■"/'""" "I ''"' Most of the works dealing with this group of animals are purely faunistic and descriptive 



of the species. The most important works on this subject are those of C. Glais, 1891a and 



(!. \V. MiEEKli, 1906a, b, c and 1908. 



Pdsirnih-ynnn/ 'p|,,, „|.|j^ features of the postembryonal development of the Halocyprids have 



"'""'""""■ become rather well known hv ('. Cl.Ars's works of 189.3 and 1894 and G. \V. Ml'I.I. Eli's works 



