EXPERIMENT STATION BULLETINS. 269 



In Agar Flutes — The gonidfa show germination to be well started after 

 eighteen hours, usually one germ tube being put out at a time. Later 

 a second tube usually is put out opposite the first. The gonidia early 

 nearly disappear, being marked by granular protoplasm, the tube being 

 hyaline at this stage. After twenty-four hours branching commences, the 

 older parts being granular, the growing parts remaining for the most 

 part hj^aline. The branches start at a wide angle, often being slightly 

 constricted at the base. This branching under the surface goes on rapidly. 

 After about fortj-four hours,, threads commence to show above the sur- 

 face of the agar. Xo septa are visible and vacuoles are very few and far 

 between. 



The aerial threads bear gonidia in abundance, singly on short ster- 

 igmata, placed at right angles to the thread. These sterigmata are 

 placed at short intervals, sometimes singly, sometimes in pairs, and 

 sometimes in groups of three. See Fig. 18. 



Hyphal Bodies — If the body of a Lecanium, affected with this para- 

 site, be examined early in the course of the disease, before any growth 

 has appeared on the surface, it will be seen to contain many hyphal 

 bodies. Fig. 18. These are fusiform bodies, non-septate, containing gran- 

 ular protoplasm, and of varying size. Some of them are likely to 

 be undergoing germination, putting out one or two slender, hyaline 

 germ-tubes at one or both ends. These germ-tubes grow just as do 

 those produced by the gonidia. 



In studying this interesting form, one is at all times reminded of 

 the early stages of Gordyceps clavulata (Schw.) Ellis. Both work on 

 Coccidae of the genus Lecanium. C. clavulata passes through the floc- 

 culent stage described here but does not stop at that point, instead, it 

 develops true Isaria sporophores, and later true Cordyceps heads with 

 spores, at the apices of the Isaria sporophores, lecanifera, instead, 

 stops at the first stage, producing no Isaria sporophores, so far as is 

 known to the writer, and no perfect stage. The two species resemble 

 each other very closely and differ only enough to make sure that tliey 

 are not the same. Hyphal bodies, very similar in form, are found in 

 the bodies of the affected insects, being septate in C. clavidata and non- 

 septate in lecanifera. The gonidia are borne on flask-shaped sterig- 

 mata in both cases, being placed singly at intervals along the thread 

 in clavulata, and in groups of two or three in lecanifera. The latter 

 species grows much more freely in culture than clavulata, although 

 both have yet refused to produce gonidia in agar agar. 



THE MAPLE COTTONY PSEUDOCOCCUS. 



Pseudococcus acericola King, 



A coccid or scale-insect of more or less economic importance has 

 been found this year, for the first time in our State. This new insect 

 works on maples, and appears as white, cottony or menly spots on the 

 leaves. The insects spread rapidly, as is the case with most scale-in- 

 sects, but are found in widely separated places. They are no doubt 

 carried on the feet of birds, and as the females have l^gs and are capa- 

 ble of moving about all their lives (at least up to the time when the 

 eggs are laid) this is easily done. The writer has found this insect 

 twice, once an isolated colony at Ypsilanti, Mich., on a few trees, and 

 once on a single tree at Ithaca, N. Y., in Six-Mile gorge. 



