Subordo II. 



PHYLLOPODA. 



Character. Branchiopoder af meget foi'skjellig 

 Kropsform, dels uden, dels med Rygskjold, det sidste 

 undertiden ndviklet i Form af 2 voluminose, det 

 hele Dyr omsluttende Valvler. Legemets Segmenta- 

 tion forskjellig hos de forskjellige Former. Øinene dels 

 stilkede, dels sessile, undertiden næsten sammensmel- 

 tede; et mediant Enkeltoie ^ocellus) tilstede. Folerne 

 i Regelen meget ulige ndviklede; Iste Par som oftest 

 meget smaa og udelukkende sensitive; 2det Par 

 af forskjellig Bygning, snart rudimentære (hos det 

 voxne Dyr), snart udviklede til kraftige 2grenede 

 Aarer, eller til tangformige Griberedskaber (hos 

 Hannen). Dverlæben vel udviklet, klapformig; Under- 

 læben i Regelen manglende. Kindbakkerne hos det 

 udviklede Dyr uden Palpe. To Par Kjæver tilstede, 

 begge smaa og af forholdsvis simpel Bygning. Alle 

 bag Munddelene folgende Lemmer respiratoriske, af 

 tilnærmelsesvis uniform Bygning og bladdannet lap- 

 pet Form; deres Tal meget forskjelligt, undertiden 

 abnormt stort. Ud vikl ingen i Regelen en compli- 

 ceret Metamorphose, begyndende med et frit Nauplius- 

 Stadium. Indlandsdyr. 



Bemærkninger. Denne Underorden omfatter et 

 ikke meget stort Antal Dj-reformer, der imidlertid 

 viser meget væsentlige Forskjelligheder, saavel hvad 

 det jalre Udseende som den indre B3rgning angaar. 

 Hvad der hovedsageligt characteriserer denne Af- 

 deling af Branchiopoder, og har givet dem sit Navn, 

 er Structuren af de bag Munddelene folgende Lem- 

 mer, der alle viser et lignende bladformigt og lappet 

 Udseende som de til Midtkroppen hos Phyllocariderne 

 horende saakaldte Branchialfodder. Da de tillige i 

 sin Function er udpræget respiratoriske, benævnes 



Sudordo II. 



PHYLLOPODA. 



Characters. Branehiopods of very various 

 shape, partly without and partly with carapace, 

 the lastnamed sometimes developed in the form of 

 2 voluminous valves enveloping the entire animal. 

 The segmentation of the body different in the 

 various forms. Eyes partly pedunculated, partly 

 sessile, sometimes nearly coalescent; a median single 

 eye (ocellus) present. Antennae, as a rule, very 

 iinequally developed; 1st ]iair most frequently very- 

 small and exclusivel}' sensitory; 2nd pair of vari- 

 able structure, sometimes rudimentary (in the adult 

 animal), sometimes developed to powerful, 2-branched 

 oars, or to pincer-shaped prehensile ajiparatus (in 

 the male). Anterior lip well developed, flap-formed; 

 posterior lip, as a rule, wanting. Mandibles, in the 

 developed animal devoid of palpi. Two pairs of max- 

 illae ]iresent, both small and of relatively simple 

 structure. All the appendages placed behind the 

 oral parts respiratory, of ap])roximately uniform 

 structure and leaf-formed shape; their number very 

 variable, sometimes abnormally large. The de- 

 velopment iTsually a complicated metamorphosis, 

 commencing with a free Nauplius-stage. Inland 

 animals. 



Remarks. This sub-order includes a not very 

 large number of animal forms, which exhibit, how- 

 ever, very material divergencies, both in respect of 

 the external appearance as well as in the internal 

 structure. What chiefly characterizes this division of 

 Branchio])ods and has gevin to it its designation is, 

 the structure of the appendages placed behind the 

 oral parts, which all exhibit a similar leaf-shaped 

 and lobed appearance as the so-called branchial-feet 

 pertaining to the mesosome in the Phyllocarida. 

 As they are, besides, in their function prominently 



