26 



tive Fluted or Cottony-cushion Scale (Icerya purcliasi), still of course 

 there is abundant room for this second species to aid in this commend- 

 able work. Being much smaller than the Vedalia and. not passing 

 through its changes anymore rapidly, it is very doubtful whether the 

 Novius could have accomplished the same work in the same time that 

 the Vedalia did in California. 



It is very probable that four other kinds of beneficial insects, the 

 Zeis conformis, Alesia fromata y the reddish-yellow ladybird with six 

 elytral black spots, and the small black one with two large elytral red 

 spots, are also established here, but these were received in such small 

 numbers that some little time must elapse before they will have multi- 

 plied sufficiently to be met with except after a long and careful search 

 for them. It is also possible that the Cryptolsemus and two or three 

 species of Scymnids, as well as the Thalpochares, may yet be found to 

 have gained a foothold here, but this can be determined only after the 

 lapse of several months, or perhaps even longer than this. I have 

 already alluded to the fact that the Scymnus lophanthce was also among 

 the specimens introduced, but this can hardly be considered an intro- 

 duction in the same light as the other species, since it was already 

 established here before these later specimens were received. 



I have not observed that either of the two species of fungi received 

 from Australia, the one attacking Lecanium olew, the other on Aspidi- 

 otus aurantii, has spread to the healthy scale insects, but of course it 

 is possible that the spores of these fungi may remain dormant until the 

 wet season sets in. 



THE WALNUT SPAN-WORM. 



The English Walnut is quite extensively grown in certain localities 

 in this State, and, in proportion to the amount of care bestowed upon 

 it, yields a larger revenue than almost any other tree grown upon this 

 coast. It is remarkably free from the attacks of insects, those here- 

 tofore known to attack it never occurring in sufficient numbers to cause 

 any widespread destruction of the trees or nuts. Two years ago, 

 however, a span-worm appeared in such large numbers in a certain 

 locality that many trees were almost completely defoliated by it. 



The first intimation I received in regard to the appearance of this 

 new pest was a letter from Hon. Ellwood Cooper, of Santa Barbara, 

 under date of April 29, 1890, and which reads as follows: 



I send you by this mail a box of worms. Please write me by return mail what 

 they are, whether from a moth, miller, butterfly, or beetle. What kind of eggs, and 

 the time required for them to hatch ? When do the worms go into the pupa state, 

 and where? Nothing of this kind has ever been seen on the ranch before. My fore- 

 man said he saw the very small worms about ten days ago. I had never seen any- 

 thing on the walnut trees, and hence did not at once go to look after them. A few 

 days later I made an examination, but could find no eggs, yet very minute worms. 

 I sent the foreman, but none could be found. The eggs must have been laid on the 

 twigs, because the leaves have only been out about fourteen days. About one week 



