114 THE AMERICAN BOTANIST 



moths are known, but the larvae have never been seen, and it 

 is a matter of conjecture as to just where they pass their early 

 days. One species, Papaipcma rutila, the type of which is in 

 the British Museum, was collected somewhere in Illinois in 

 1853 and has never been seen since. Its larvae may have fed 

 on some wild plant that has since become rare, and in this 

 way become practically extinct since a large number of the 

 borers are restricted to a single species of food plant and die 

 when its food plant disappears. Dr. Henry Bird of Rye, N. 

 Y., who is making a specialty of these insects writes as fol- 

 lows regarding the plants upon which they feed. "The list 

 of foodplants run from Composites to Cryptogams, so there 

 is no particular family to count on, it is simply a case of search- 

 ing. As you may gather, particular floras limit the zone of 

 certain species of these moths; in the stems and roots of the 

 salt-water goldenrod (Solidago sempervirens) , a certain 

 species bores in its larval existance and is confined in its flight 

 as a moth to the fringe of Atlantic seaboard where this plant 

 occurs. Species boring ironweed follow its distribution ; sev- 

 eral of the sunflowers serve more widely distributed species. 

 Podophylluin peltatniii and Ritdbekia laciuiata are foodplants 

 with species west of the Alleghanes but have not been found 

 infested in the East. Sarracenia purpurea and 6". Drwnmondii 

 afford another range from Ontario to the Gulf, where bog 

 conditions prevail. Among the ferns Onoclea scnsibilis and 

 Pteris aqiiilina support two primitive types over an extended 

 area; Cirsium occidcntale is preferred by a Pacific coast spe- 

 cies I have just described. Aqiiilegia, Eiipatorium, Thalic- 

 triim, Collinsonia, Ambrosia, Arctium, Heracleum, Zida, 

 Humidus, and many more furnish other species with susten- 

 ance." As soon as the larvae hatch they begin to bore in 

 stems or roots. Some change to chrysalids within their gal- 

 leries and these have the instinct to make a door to the outer 

 world through which the moth may escape. In all cases the 



