USED IN ENTOMOLOGY. 135 



nective tissue lying above the central nervous system in adult Lcpidoptera; 



also to a sinus or vessel acting as a ventral heart. 



Supra-spiracular line: in caterpillars, margins the spiracles superiorly. 

 Supra-stigmatal line: supra-spiracular lines. 



Supra-triangular cross-veins: in Odonata, cross the supra-triangular space. 

 Supra-triangular space: in Anisoptcra, an area just above the triangle, 



occupying nearly the same position as the quadrilateral of Zygoptcra: 



= hyper-trigonal space. 

 Suranal: = supra-anal. 



Suranal plate: the middle dorsal plate attached to the 10th abdominal seg- 

 ment of the c? grasshoppers, above the anal opening : a supra-anal tergite 



of a caterpillar. 

 Sursum: directed upwardly. 

 Suspensi: the chrysalids of butterflies that are suspended by the tail only: 



see succincti. 

 Suspensoria: are those muscles or ligaments that hold the viscera and other 



internal structures in place. 



Sustentors: the two posterior projections of a butterfly chrysalis. 

 Suture: a seam or impressed line indicating the division of distinct parts of 



body wall : the line of junction of elytra in Coleoptera, 

 Suturiform: an articulation soldered together so that only a slight impressed 



line is visible. 

 Swarming: the concerted departure from a hive of a large number of worker 



bees, accompanied by a queen ; this forming the nucleus of a new colony. 

 Swimmerets: gill or plate-like structures in the aquatic larva? of some 



Neuroptera, serving as oars or organs of locomotion. 

 Swimming paddles: terminal appendages of mosquito pupae. 

 Swoked: smoky, suffused with gray or blackish. 

 Sylvan: species inhabiting forests or woodland areas. 

 Symbiogenesis: the method of origin of social symbiotic relation among 



ants and other insects. 

 Symbiosis: a life relationship existing between different kinds of animals or 



plants, or between animals and plants : true symbiosis is where both parties 



to the relation benefit : see also parasitism, commensalism. Among the ants 



social symbiosis exists in its most highly developed form and distinctive 



terms have been proposed for the various types of relations : 



Calobiosis, is that association in which one species, often only the female, 



lives in the nest of and at the expense of another species, either for a time, 



= temporary or altogether, = permanent calacobiosis. 



Cleptobiosis, is where one species of ant lives in or near the nest of 



another, preying upon its larvae or pupae or stealing the food supply. 



Dulosis, is that mingling of colonies which owes its origin to the en- 

 slavement of one species by another. 



Hamabiosis, is that relation where two species of any insects, one of 



which may be an ant, live side by side without obvious motive or known 



advantage to one or both. 



Lcstobiosis, is where the workers of one ant colony " hold up " those of 



another species and rob them of the food they are carrying to the nest. 



