STARCH. 187 



(i.) Glucose, dextrose, grape sugar. (v.) Acrose. 



(ii.) Fructose, levulose, fruit sugar. (vi.) Mannose. 

 (iii.) Galactose. (vii.) Formose. 



(iv.) Sorbinose. ( vm -) Methose. 



(b) The Saccharoses or Hexo-bioses, C^H^On : 



(i.) Saccharose, saccharobiose, or cane-sugar. 



(ii.) Lactose, lactobiose, or milk sugar. 

 (iii.) Maltose, maltobiose, or malt sugar. 

 (iv.) Melibiose. 



(v.) Trehalose, mycose. 



(c) The Hcxo-trioses, C 18 H 32 16 : -- 



Raffinose. 



Resembling the group of carbohydrates are certain other 

 substances which occur in plants. Of these the following may 

 be mentioned : 



(1) The Pentoses : 



(i.) Arabinose, C S H 10 6 , and araban, (C 5 H 8 O 4 ) n . 

 (ii.) Xylose, C 5 H 10 5 , and xylan, (C 6 H 8 0,) n . 

 (iii.) Ribose, C.,H 10 6 . 

 (iv.) Rhamncse or methyl arabinose, C 6 H 12 O 6 + H 2 0. 



(v.) Fucose, C (; H 12 5 . 

 (vi.) The " furfuroids" (Cross and Bevan). 



(2) Certain Polyhydric Alcohols : 



(i.) Mannite or Mannitol, C 6 H 8 (OH) 6 . 

 (ii.) Dulcitol, C f) H 8 (OH) 6 . 

 (iii.) Sorbitol, C 6 H H (OH) 6 +H a O. 

 (iv.) Perseitol or perseite, C 7 H 16 O 7 . 



(3) Liyiione. 



(4) Pectin substances : 



(i.) Pectose, C^Ar (?). 



(ii.) Pectin, C 2S H 42 24 , or C^ftA,,. 

 (iii.) Pectic acid, C. 2S H 40 2(5 , or C M H 44 W . 

 (iv.) Pectous acid, C 2S H 42 O 25 . 



A. THE AMYLOSES OB POLYSACCHABIDES. 

 Starch or amylum, (C (i H 10 O 5 ) n . This substance is very 

 widely distributed in plants and serves as a reserve material 



* The composition of the pectin bodies is not well known ; the above formulae are 

 not trustworthy. 



