A CENTIPED (Scolopendra heros). 



Phylum X, ARTHROPODA; class 3, MYRIAPODA; order 2, CHILOPODA. 



HABITAT. Centipeds are of world-wide distribution, some species 

 being adapted to the higher latitudes or elevated cold regions, while 

 others, particularly the larger species, abound in the tropics. They 

 are all terrestrial. We may look for them under stones, logs, and 

 leaves or the bark of decaying trees and stumps. One genus 

 Scutigera frequents cellars and the darker corners of houses. The 

 food of Centipeds is mainly insects, spiders, and snails. 



APPEARANCE. Centipeds are worm-like animals with a great many 

 legs. In color they range from straw-yellow to various shades of brown 

 or reddish. They can be distinguished from the Millipeds, their near 

 relatives, by their flattened bodies, by their swifter movements, and by 

 their smaller number of legs. The Millipeds are more nearly cylindri- 

 cal, have two pairs of legs to most of the segments, and usually curl 

 up or move slowly away when disturbed. Scolopendra heros is one 

 of the larger species, measuring from three to five inches in length. 



Technical Note. Centipeds may be collected in the situations mentioned 

 above and placed in alcohol or formalin for class use. Fresh speci- 

 mens can be killed in a cyanide bottle. As the bite of these creatures 

 is poisonous, they should be picked up, when alive, with long forceps. 

 Fasten the specimen to a piece of board or sheet cork, by inserting a 

 pin near each end, and study with a hand lens. Other species than 

 the one treated in this exercise will answer the purpose very well. 



EXTERNAL FEATURES. The following notes will serve as a guide in 

 determining relations and parts: 



a) The comparatively simple or generalized type of structure is appar- 

 ent in the similarity of the numerous segments into which the 

 body is divided. Two body regions may be recognized, a head 

 and a trunk. Is there any indication of a division of the latter 



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