542 103. CHAEACEJE. 



nent than the primary, many setaceous spreading spines, branch- 

 lets 7 9-jointed, stipulodes prominent, bracts on both sides of 

 the branchlet 8 10 exceeding the ovoid nucules of 10 or 11 

 spires. 2?. JB. 463. Usually very large, much incrusted, 

 often 3 or 4 feet long. Sterile branchlets 3 4 inches long. 

 Spines variable in quantity and length. (J3. macracantha (Braun) ; 

 spine- and bract-cells very long. y. gymnoteles (Braun) ; spine-cells few, 

 branchl. with several ecorticate joints. 5. C. horrida ( Wahlst.) ; small 

 and compact, spine-cells short patent very numerous, branchl. straight 

 spreading. Subsp. rudis (Braun) ; st. more slender secondary cortical 

 cells very strongly developed almost hiding the primary (spine-bearing) 

 series.] Ponds and ditches. [& Doubtfully British.] VI. E. S. T. 



7. C. polyacaritha (Braun) ; st. stout, primary cortical cells 

 more prominent than secondary, many setaceous fascicled 

 spreading spines, 8 10 branchlets of 6 8 joints, stipulodes 

 long slender, bracts 6 10 exceeding the ovoid nucules of 12 or 

 13 spires. J. of E. xviii. t. 208. Ail. PL Par. t. 38. B. f. 3. 

 Very spinous, much incrusted ; smaller, more spinous, with 

 shorter branchlets but longer internodes than C. hispida. 

 Ponds and ditches. VI. E. S. 1. 



8. C. bal'tica (Fr.) ; st. stout finely striate flexible pri- 

 mary cortical cells more prominent than secondaiy, spines 

 many slender spreading, branchlets 6 9 patent many-jointed, 

 etipulodes slender, bracts whorled long exceeding oblong nncules 

 of 10 15 spires and spreading crown. [J. ofS.xix. (1881), t. 224, 

 1.] Pale green, not incrusted. Moderately spinous. Upper 

 part of branches not coated. Bracts very long. Lowest nodes 

 t with bulbils. Ponds. Kynance Vale, Cornwall. [Dorset. 

 Orkney. Guernsey.] VIII. * E. 



b. Dioecious. 



9. C. tomentosa (L.); st. thickened upwards twisted, primary 

 cortical cells very prominent, spines few short stout scattered, 

 branchlets 5 7 rather incurved of 4 6 long joints the upper 

 joints not coated but inflated, stipnlodes usually short and thick) 

 bracts usually 5 very thick the lateral exceeding the ovoid 

 nucules of 12 14 spires the others falling short of them. Hook. 

 Icon. PI. 532. Opaque, greenish white when fresh, usually 

 much incrusted. Spines rather whorled, very short, acute. 

 Upper joints of branchlets remarkably inflated and lengthened 

 in our plant. Shannon Lakes. I. 



ttt St. with 3 roivs of cortical cells to each branchlet. 



10. C. as'pera (W.) ; dioecious , st. slender flexible with slender 

 acute spreading spines, branchlets 6 9 rather incurved or straight, 



