Die sogenaamde stinkkliere by stinkbesies is spesiale kliere w a t gifgas uitskei en w a t deur die besie vir verdediging gebruik w ord. Hulle openinge is by die nim fe (onvolwassenes) gelee op drie of vier knoppies op die dorsale deel van die agterlyf. By volwassenes, w aar die agterlyf deur vlerke bedek w ord, is die kliere in die bors (thoraks) gelee met openinge (osteole) aan die s y k a n t e n e t v o o r di e a g t e r p o t e . Di e stinkkliersekresie w o rd met 'n sterk spuitaksie tot 300 mm ver uitgespuit. Dit brand die vel e n o e e n kan volgens oorlew ing tydelike blindheid by die
mens veroorsaak. Die stinkklier produseer n vlugtige mengsel w a t tot 18 chemiese stow w e kan bevat en w a t by i n a s e m i n g deur voornemende predatore die senuweestelsel kan verlam. Dit neem etlike dae v ir die sekresie om weer in die klier te vorm. IqTTTiI
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F A U R E J C 1 9 4 4 P e n t a io m id b u g s a s h u m a n fo o d J o u r n a l o f th e E n to m o lo g ic a l S o c ie ty o f S o u th e rn A fr ic a 7 T 1 0 -1 1 2
H O L M . E & DE V IL L IE R S . W M 1 9 8 3 O n s v ie I n s e k t e N a s io n a le B o e k d ru k k e ry G o o d w o o d
SPECIAL "LIVE EXHIBIT" OF FOSSIL PREPARATION
M any people w h o visit museum s have seen bones and skeletons of dinosaurs and other w eird prehistoric creatures on display, but very few are aware of the trem endous a m oun t of technical w ork w h ic h has to be undertaken before a fossil bone is " f it to be displayed". In most cases the presence of a fossilized skull or skeleton in a rocky outcrop in the field is recognisable only to someone w h o is an experienced fossil collector. A lth o u g h there are exceptions, a fossil is usually only exposed as a few sm all bones p rotrud ing from a rock. Such fossil-bearing rocks are then taken back to a palaeontological laboratory w here the bones are carefully and painstakin gly removed from the rock by skilled palaeontological technicians w ith the aid of fine air-driven engravers and dental drills. This laborious process is extrem ely slo w and a single skull may take several m onths to prepare.
In Janu ary visito rs to the National M useum were given a "be h in d the scenes" look at how fossils are removed from the rock. Rocks w ith pieces of bone protrud ing f rom them a sthey were found in the field were on display, as w e ll as fu lly prepared skeletons and skulls of the National M useum 's most prized and valuable fossils. As th is 'w o rk in g ' e xhibit w as a great success and served to attract num erous visitors, sim ila r exhibits are planned at the N ational M useum durin g the school holidays later th is year.
M rs Z u b i G regorow ski a n d M r Christian N y ap h u li dem o n stratin g h o w the rock is carefully chipped from an
ancient d inosaur bone. ,
Ip h o to D ie V o lksb fa d )
