A^D DEVELOryiEST OF COMYy lAFELlX. 



23' 



toucliing the path of the insect as it progressed. Many coccids were examined, and, 

 when a suitable one was found, the parasite turned its head towards the anterior 

 extremity of the coccid, and, resting wdtli all its feet upon the body of the latter, 

 inserted its ovipositor into the centre of the thoracic area; it then slowly moved its 

 abdomen up and down, and apparently laid its eggs in the puncture ; the parasite then 

 Avithdrew its ovipositor, and, turning round abruptly, feeling its way again with its 

 antennae, seized with its jaws the lips of the wound made by its ovij^ositor, and distinctly 

 closed them upon it and ajiparently jiressed the edges together ; finally it passed the 

 palpi over the wound, and tlien left the coccid to its i'ate." 



These insects do not — as is the case with so many species — seek the light ; on tha 

 contrary they prefer tlie shadow. I tested this many times by having them in a glass 

 vessel, of which one half was illviminated and the other half shaded ; they always left 

 the light for the darkened end. This behaviour is all the more unexpected seeing that in 

 the sunlight their activity was always so marked, but it may be that they were resting 

 and therefore jjreferred to be in the dark. Tor the most part, they sit inactive on the 

 l^lant on which they are bred ; they seldom ofl'er to leave it, flying but rarely and tlien 

 only under the stimulus of strong sunsliine ; such flights are short, never exceeding the 

 distance between one fern-frond and the next. Their most usual mode of locomotion is 

 walking at a relatively rapid rate, supplemented by sudden jumps, effected doubtless by 

 the powerful tibial spurs of the second legs ; by this leaj) they often cover a distance of 

 one or two feet. This rapid running movement gives them a certain likeness to ants, 

 which they resemble curiously in colour and size, for their wings are carried folded flat 

 upon the dorsal surface and are inconspicuous. The antennae are constantly feeling 

 and moving, as is also the case with ants, and at first sight this motion is sufficient to 

 suggest the resemblance. 



(c) Economic Aspects. — From an economic point of view Coini/s hifelix is of signal 

 importance inasmuch as it destroys one of our most injurious sc'ile-insects. Goccidn3 

 attack a great many plants of commercial value and do immense damage ; usually the 

 horticulturist combats their ravages by means of spraving Avith insecticides, but the 

 question of parasites is of the greatest importance. In a preliminai'y paper on 

 the "Economic Importance of the Parasites of Coccida;'' (17), referring to G. InfelLv, I 

 have said that " as far as I can judge from the facts that have come under niy observation, 

 I am led to rate very highly the value of these parasitic Ilymenoptera as destroyers of 

 Coccid pests. In the case of L. hemisphcbricHm, King's statement that it is one of the 

 commonest pests in greenhouses applies to the district j-ound Cambridge as Avell as to 

 the United States, and the pest is satisfactorily controlled by tlie parasite. If the 

 parasite is not found in other districts where the scale is injurious, it should be introduced 

 there. Considerable difliculty has been experienced in the attempts to distribute the 

 predaceous enemies, but in the case of the internal parasites, the task is much simj)ler, 

 and success will be easier to attain, for it is only necessary to transmit a small plant 

 bearing a few parasitized Coccidic. Prom my work on this species I am led to believe 

 that the EncyrthicB are remarkably tenacious of life in their early stages." As regards 

 the quarantine regulations that are so strictly enforced in many parts of the world, I 



