ART. 18. 



ENTOMOSTRACA FROM COLORADO DODDS. 



3 



in the mountains, and (3) 9 species found in both groups of lakes. 

 The third group includes the euthermic species, those which are able 

 to live in both warm and cold water, while the first and second 



meters 



Diaptomus ahoshone ..-••- 

 Mactothrix montana <.»•--- 



Latond sttifera ,..*,-- 



PleUTOXUS procuTtaius • 



Branchineda coloraJensis 



Diaplomus nuJus 



Diaptomus Uplopus ---.--- 



Alona affinis .-..- 



Alona reclaniula 



Daphnia longispina - - • 



Daphnia pulex »...- 



Ceriodaphnia rdiculala 



MacTolhrix hirsuticarnis 



ChyJorus sphaericus 



Cyclops albidus .-------- 



Cychps hicuspidatus ------ 



Cyclops serrulalus ..--•*--- 

 Cyclops eiridis -----.•---- 



Craploleberis lesludinaria 



Simocephalus cetulus ------ 



Scapholehtris mucronala - - - - 



Bosr^ina longiroslris ------ 



Dunheoedia crassa - - -.- • - - 



PleUTOXUS adunclus - » 



Ltydigca quadrangular is - - - - 



Diaplomus clacieeps ------ 



t)iaptomus siciloiifes --,---• 

 Diaptomus athuquerquensis - - 

 Diaptomus washingf.oner(sii • - 

 Diphanosoma hrachyutum - « • 

 Ceriodaphnia quaJranguh ^ ' 



Fig. 1.— Graphic representation of altitudinal range of the species of entomostraca collected 



BY H. L. SHANTZ in the PIKE's PEAK REGION. THE SOLID BLACK PART OF EACH BAR REPRESENTS THE 

 RANGE OF ALTITUDE COVERED BY THE PRESENT COLLECTIONS, THE OPEN PART THE EXTENSIONS OF RANGE 

 BY MAKING USE OF ALL OTHER RECORDS FROM THE STATE OF COLORADO. 



groups are composed of stenothermic species, which are more nar- 

 rowly limited to water of about the same temperature, the one group 

 to colder waters, the other to warmer. These three groups are 

 clearly shown in Figure 1 . The significance of these records becomes 



