342 



GLOSSARY. 



lamina : the thin flattened por- 

 tion of a leaf ; the blade. 



lanceolate : narrow and pointed ; 

 lance- shaped. 



larva : the active young of an 

 animal when it is in structure 

 and habits unlike the parent, 

 e.g. caterpillars or tadpoles. 



lateral line : a line which may 

 be seen on the side of a bony 

 fish's body. It is sensory in 

 function. 



legume : see pod. 



lenticel : a place in the bark of 

 a tree where the cork cells are 

 loosely packed, permitting in- 

 terchange of gases. 



lipochrome : a group ot pig- 

 ments occurring in organ- 

 isms. They vary from red to 

 yellow. 



lymph : that part of the blood 

 plasma which conveys nourish- 

 ment to the tissues. It is the 

 intermediary between the tis- 

 sues and the blood. 



Mendel's law : a law of inherit- 

 ance according to which 

 mated individuals exhibiting 

 certain mutually exclusive 

 characters give rise to off- 

 spring amongst which these 

 characters are distributed in 

 definite proportions. 



metamorphosis : the change of 

 form undergone by some 

 animals before reaching the 

 adult state. 



mollusca : soft-bodied inverte- 

 brate animals, mostly with 

 limy shells, e.g. Snail, Oyster. 



monocotyledon : having only one 

 seed leaf (sometimes a second, 

 in a vestigial condition, is pre- 

 sent). 



mycelium : the substance of a 

 fungus distinct from repro- 



ductive parts, consisting of a 

 mass of interlacing branching 

 threads (liyphae}. 



nectary : a part of a plant pro- 

 ducing sweet stuff for the 

 attraction of visitors. 



nut : a dry non-splitting fruit 

 having woody walls, and con- 

 taining a single seed.. 



obovate : a reversed ovate form ; 

 broadest at free end, e.g. 

 leaves of Alder. 



orbicular : rounded, approaching 

 the circular in outline. 



ovary: the hollow part of the 

 carpel or carpels in which the 

 ovules develop. 



ovate : approaching the shape of 

 an egg in outline. Applied to 

 leaves which ar*e rounded, 

 longer than broad, and broad- 

 est towards the base. 



ovule : the developing seed, prior 

 to fertilisation. 



palea : the scale or bract ad- 

 jacent to the flower in a grass 

 (the glumes occur outside the 

 palea). 



palisade layer : the close - set 

 layer of cells, longer than 

 broad, lying below the upper 

 epidermis of a leaf. 



palmate : shaped like the palm, 

 with spreading lobes. 



pappus : the circlet of soft hairs 

 seen on the fruits of many 

 compositae, e.g. Dandelion. 

 It represents the calyx. 



pectoral : relating to the breast, 

 e.g. pectoral muscle; pectoral 

 fin. 



pedicel : the stalk of a single 

 flower. 



