ECOLOGICAL PAPERS. 



127 



Ecological conditions similar to the various habitats in Slough 93 

 were found in the fifty-sixth, ninety-second and ninety-fifth 

 sloughs and a series of collections has been made in each of these. 

 The plans for the work this spring include the making of a topo- 

 graphical map of this region. The mapping of the sloughs is to be 

 based largely on new surveys made for that purpose. 



QUALITATIVE SUCCESSION. 



The first work attempted was to find the qualitative succession 

 during the year. The results so far obtained are listed in Table I. 

 Animals may have been present when they are not recorded in the 

 list, but if they were, they must have been much restricted in 

 numbers as well as in habitat. 



TABLE I 



GROUP NAME SCIENTIFIC NAME. 



2 > § 



> U) 



^ ^ 

 ^ w 



o a: 



o o 



Agrionidae larvse 



Agrionidae adults 



Backswimmers Plea striola (Felt) 



Xotonecta undulata (Say) 



Branchipus • 



Caddice fly larvae 



Canthocampus * * 



Chauliodes Chauliodes rastricornis (Rambur) .... • 



Chironomidae larvae * 



Cladocera 



Crayfish Cambarus immunis (Hagen) * * 



Cyclops • * 



Diaptomus * * 



Diptera Corethra larvae * 



Stratiomyiidse 



Donacia sp. 



Dragonflies Anax Junius (Drury) 



Libellula pulchella (Drury) 



Lestes vigilax (Hagen) 



Lestes rectangularis (Say) 



Sympetrum obtrusum (Hagen).... 



Sympetrum rubicundulum (Say).... 



Aeschnidae larvae 



Libellulidae larvse ♦ * 



Dytiscidae Ilybius sp 



Hydroporus modestus (Aube) * * 



Desmopachria convexa (Aube) 



Colymbetes sculptilis (Harr.) 



Laccophilus sp 



Graphoderes sp 



Larv» sp 



Ephemeridae Siphlurus sp * 



Flatworms * * 



Frog Rana sp. adult * 



Rana sp. larvae * 



.Acris gryllus (Le Carte) 



Gammaridae Eucrangonyx gracilis (Smith) * ♦ • 



Giant water bug Amorgius americanum (Leidy) 



Gyrinidae Dinentes hornii (Roberts) * 



Heterotrichidae 



Hydrophyllidae Berosus sp 



Larvae 



Isopoda Asellus communis (Say) 



Mancasellus danielsii (Richardson) 

 Leech Erpobdella punctata (Leidy).... 



Glossiphonia heteroclita (Lin.).. 

 Lymnaeidae Lymnjea reflexa (Say) 



Planorbis exacutus (Say) 



Planorbis trivolvis (Say) 



Planorbis deflectus (Say) 



Segmentina armigera (Say).... 



? • 



* * * * • * • 



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