The Cabbage Root Maggot. 503 



lying within or which may have recently left through a distinct exit hole to 

 go into the soil to transform. Thus, these galls made by weevils ought to be 

 easily distinguished, wherever found, from the gall-like swellings of the 

 Club root* 



Previous to 1876, in the books and newspaper writings of American gar- 

 deners, the Club-root of cabbages was usually associated with, and recorded 

 as being caused by, the Cabbage Root Maggot. Peter Henderson was one of 

 the foremost believers in this idea ; and in his 1887 edition of " Gardening 

 for Profit," although he seems to have abandoned his idea of its being caused 

 by this maggot, yet he attributes Club-root to an insect, but does not say 

 what one. The disease caused much speculation among scientific observers 

 for many years before its true cause was discovered. The lives and habits of 

 the insects sometimes found accompanying the disease were studied carefully, 

 but all efforts failed to convict any of them of being the author of the injury. 

 Finally, after three years (1873-1876) of exhaustive and painstaking labor, 

 an European botanist, M. Woronin, explained the nature and cause of the 

 disease. He showed it to be caused by a low form of fungous growth, one of 

 the Slime Moulds {Plasinodiophora brassicce). Other investigators have 

 since studied the disease and all agree that it is primarily caused by this 

 Slime Mould. 



Thus, while there is no doubt that the Cabbage Root Maggot 

 is often found attacking Club-rooted cabbage, it is also a fact that 

 the maggots destroy thousands of plants where there is no trace 

 of Club-root ; and it is also true that the Slime Mould of Club- 

 root is the sole cause of the death of thousands of plants in fields 



*Ceutorh\nchus rapne Gyll. has been recorded injuring cabbages in Missouri by Miss 

 Murtfeldt (Rept. of U. S. Entomologist for 1S8S, p. 136; also Bull. 30 of the Ent. Div., p. 50). 

 We have found a closely allied species, " perhaps new " says Dr. Horn, doing great damage 

 in fields of seed cabbage on Long Island. The grubs burrow in the pith of the seed stalk 

 and its branches. Often hundreds occur in a single stalk, and sometimes whole fields of 

 seed cabbage are ruined by the stalks wilting and breaking over just before the seed begins 

 to mature ; thus nearly the whole crop of seed has sometimes been lost by the depredations 

 of this Seek-stalk Weevil (Ceutorhynchus sp.). We have found what is probably the same 

 species of insect exceedingly numerous here at Ithaca boring in the stems of the Shep- 

 herd's Purse, the Common Winter Cress, and the Hedge Mustard ; in fact, nearly every 

 plant of the above weeds found near ihe insectary in July had their pith liddled by the 

 maggots of this borer. The cabbage seed growers on Long Island thought that this stalk 

 borer was the Cabbage Root Maggot ; the maggots having simply continued on up the stem 

 into the pith of the seed stalk. We found no Cabbage Root Maggots in the seed stalk, but 

 they occurred in company with the Fringed Anthomyiian and other maggots on the buried 

 stem of the plant. 



This Cabbage .Seed-stalk Weevil is a very serious pest in this great seed region on Long 

 Island and should be carefully investigated We found it difficult to breed here in the 

 insectary, and thus far have learned but little regarding its life-history and habits. At 

 present we can suggest no more practical method of combating the pest than to keep the 

 fields free from Cruciferous weeds, and remove and burn all infected seed stalks as soon 

 as noticed ; after a little experience, these stalks can probably be easily distinguished from 

 the others. 



