. Fresh-water biology. Freshwater biology. THE FREE-LIVING FLATWORMS (TURBELLARIA) 355 83 (102) Normal eyes two or none Planaria . 84 84 (loi) With two normal eyes (sometimes with one or more irregularly placed accessory eyes) 85 85 (94) Anterior end more or less pointed with angular cephalic append- ages 86 86 (91) Anterior end bluntly pointed, angle formed by lateral margins of head not less than 60°. Cephalic appendages blunt. Body about as wide just back of appendages as immediately in front of them 87 87 (88) Angle formed by lateral margins of head much greater than 60°. Cephalic appendag
. Fresh-water biology. Freshwater biology. THE FREE-LIVING FLATWORMS (TURBELLARIA) 355 83 (102) Normal eyes two or none Planaria . 84 84 (loi) With two normal eyes (sometimes with one or more irregularly placed accessory eyes) 85 85 (94) Anterior end more or less pointed with angular cephalic append- ages 86 86 (91) Anterior end bluntly pointed, angle formed by lateral margins of head not less than 60°. Cephalic appendages blunt. Body about as wide just back of appendages as immediately in front of them 87 87 (88) Angle formed by lateral margins of head much greater than 60°. Cephalic appendages very inconspicuous, almost entirely wanting in young specimens. Planaria Joremanii (Girard) 1852. Length of mature specimens 7 to 15 mm., breadth 2 to 4 mm. Color nearly uniform seal-brown or dark gray to slate-black, with an inconspicuous gray area on each cephalic appendage. Eyes gray with a cres- cent of black pigment on the median side. Body comparatively thick. Ovaries two, ventral, somewhat lobed and situated about halfway from anterior end to pharynx. Testes four or live on each side, un- paired, dorsal and irregularly distributed from region of ovaries to posterior end of pharynx. Does not multiply by fission. Found in small streams in Mass., Penn., Md., Va., and near Washington, D. C. The species described by Curtis (1900) under the name Planaria simplicissima and later by Stevens un- der the same name clearly must be regarded as syn- onymous with the species established by Girard in 1852 under the name P. foremannii. This species also appears under the name P. lugubris in various papers dealing with the physiology of planarians. Fig. 62Q. Planaria Joremanii. {A) Outline sketch of large mature specimen: g^, genital pore; ph, pharynx: s, sensory area on cephalic appendages. X 4. (After Stevens.) (B) Sexual organs, longitu- dinal section, dorsal view; c, cirrus; J, oviduct; ^A, pharynx; 5if, seminal vesicles; /, testes; »/, uterus; V, ovary; vi, yolk glands; vl, va
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectfreshwa, bookyear1918
