427 



time were so old and disintegrated that specific determination was 

 impossible. The present season, however (May, 1895), Mr. Parish sends 

 us additional material, consisting- of sound females and eggs, from which 

 we are able to determine the species as Maskell's Pulvinaria psldii. 

 We have not been able to ascertain the date and manner of its intro- 

 duction into California. The species was possibly introduced from the 

 Sandwich Islands, or possibly also from Japan on Japanese plums. At 

 all events, Mr. Wait's account of the damage done by this insect to 

 guava plantations in Hawaii shows that it is a dangerous species, and 

 efforts should be made to stamp it out at once at San Bernardino. 



HOW HEMIPTERA FEED. 



There seems to be a very general misapprehension of the manner in 

 which the hemipterous insect draws up nourishment from animals or 

 plants. The popular conception that the plant or the larva or other 

 animal preyed upon is actually punctured by the beak, or, in other 

 words, that the beak, meaning the labium with inclosed sette, is thrust 

 for a greater or less distance into the tissue, is certainly erroneous. 

 Observations on the habits of our predaceous Hemiptera, together with 

 an examination of the structure of the labium itself, indicate that the 

 latter never enters the food, but that the puncture is made entirely with 

 the setfe applied together to form a lancet, and that the juices are drawn 

 up by suction through the labium or beak, which is merely applied 

 closely to the exterior surface. 



If a predaceous hemipteron be noticed in the act of sucking the 

 juices from some lepidopterous larva it will be seen that the latter is 

 suspended from, or is seemingly attached to, the very extremity of the 

 beak. Plants also, infested with aphides or larger Hemiptera, do not 

 exhibit the numerous large punctures which would result if the beak 

 were bodily inserted. The Cicada larva, for instance, which possesses. 

 a very large and robust beak, and which attaches itself to a fixed por- 

 tion of a root for a very long period, leaves no visible sign of puncture 

 other than a slight discoloration, which results from the entrance and 

 irritation of the almost microscopic setie. 



If observations on this point were wanting, the structure of the labium 

 itself would at once indicate that it could not be employed as a piercing 

 organ. The labium of all hemipterous insects, so far as I have examined 

 them, is clothed to and on the very tip with hairs, usually very strong 

 and numerous, projecting anteriorly, which would make the piercing of 

 any hard substance quite impossible, without tearing off' and rupturing 

 the hairs; and what is more, the beak is rarely very sharply pointed. 

 This holds true even of the predaceous Eeduviid?e, the water bugs, and 

 the animal i^arasites. In the case of the black reduviid, Melanolestes 

 picipes H. S., which often severely stings collectors, the beak is very 

 strongly clothed to the very tip with long, coarse bristles. The same 

 is true of Acanthia lectularia. In Belostoma the beak is quite smooth, 



