OF WASHINGTON. 393 



also from other woody plants. In the United States only one 

 insect has hitherto been recorded from Phoradendron viz., Le- 

 canium phoradendri Ckll., but there is in the National Museum 

 an undescribed Psyllid discovered on Phoradendron macro- 

 phyllum in California, by Mr. A. Koebele, which in the wing 

 venation differs remarkably from all described genera of the sub 

 family Psyllinse. Finally, Prof. Cockerell kindly informs me that 

 he had described three species of Coccidse as occurring on mistle 

 toe in Mexico. 



In the vicinity of our eastern cities the mistletoe is well-nigh 

 exterminated since many years or confined to the very tops of 

 tall trees, hut in the southwest these parasitic plants, more par 

 ticularly Phoradendron macrophyllum, are still extremely 

 abundant on trees growing along water courses, and the follow 

 ing fragmentary observations were made by me, in April, on two 

 short visits to the mouth of Bear Canyon 1 " in southern Arizona. 

 The majority of the more accessible mistletoe bushes proved to 

 be more or less infested by Lecanium phoradendri and, in many 

 instances, plants had been killed by the prevalance of the scales. 

 A search for Coccinellid enemies produced, after considerable ex 

 ertion, only a few specimens of Cephaloscymnus occidentalis 

 Horn.' 2 Occasionally mistletoe branches, either not or but 

 feebly infested with scales, were observed to be dead or wilting, 

 and it was found were hollowed out for a distance greatly vary 

 ing in length, according to the thickness of the twig. The author 

 of these galleries proved to be a Curculionid larva of the genus 

 Otidocephalus, the particular species being still undescribed. 

 The beetle makes its exit through a round hole at the side of the 

 twig, and the deserted gallery is then usually occupied by a colony 

 of ants, Cremastogaster sp., which attend to and protect the 

 Lecanium scales. 



The infested twig is not killed at once by the boring of the Oti 

 docephalus larva, but remains green for one season or longer, but 

 at any rate long enough to allow colonies of a Scolytid beetle to 

 undergo one or two generations in the terminal portion of the 

 twig. This Scolytid, one of the smallest in our fauna, is also un 

 described, and belongs, % far as I can make out at present, in the 

 neighborhood of Stephanoderus. It is an " inside borer," but no 

 regularity whatever can be observed in the tiny galleries, nor could 

 we see any trace of "ambrosia." The colonies are extremely 



lr This locality is situated about 3 miles northwest of the abandoned Ft. 

 Lowel, Pima Co., at the foot of the Santa Catalina Mts. ; altitude 2,900'. 



" This species was subsequently found by Mr. Hubbard and myself 

 in the Sta. Rita Mts. and at Oracle among a Lecanium scale on various 

 oaks, and among a diaspinous scale on Quercus arizonica. The eastern 

 species, C. zimmermanni Cr. feeds on Aspidtotus ancylus. For some 

 reason not yet ascertained both Coccinellids and their larvae are extremely 

 rare in spite of the abundant and apparently permanent food-supply. 



