PAPILIONINAE : PAPILIO POLYXENES. 1361 



The yellow osiuateria are protruded at rather slight provocation, but 

 rarely to their full length, unless roughly handled ; they emit a moderately 

 strong and disagreeable odor not very dissimilar to that of the bruised 

 leaves of their food plant. Fitch remarks in his manuscript : "As it walks 

 along the slender pedicels of the umbel it moves its head first to one side 

 and then to the other of the stem, attaching a slender thread of silk which 

 it spins from its mouth to the stem, to form a more secure foot-hold for 

 its feet." 



In Cuba, according to Dr. Gundlach, the caterpillars attain their growth in 

 the remarkably short time of nine or ten days, the first moult taking place 

 sometimes within thirty hours of birth. With us the larval period is often 

 four weeks. Shortly before pupation, they discharge a great quantity of 

 watery foecal matter and shrink notably in size, but they undergo scarcely 

 any change of color. Mr. Riley calls my attention to the peculiar cup- 

 shaped excrement. 



Pupation. The caterpillar entangles the anal prolegs securely in a 

 mat of silk, spins a loop in front, crawls underneath this and curves the 

 head and front part of the body so that the head strikes the surface to 

 which the ends of the loop were fastened and the cord passes between the 

 second and third abdominal segments. It remains thus for at least twenty- 

 four hours before the change to chrysalis is effected, when the thread sinks 

 so deeply in the soft pupal skin as to be firmly embedded in it when dry ; 

 it passes across the back in the middle of the metathorax, and from its length 

 allows considerable swing to the chrysalis. The chrysalis state varies 

 with the season and latitude from nine to eighteen days ; but Dr. Morris 

 has stated that one instance was known to him of its duration for two 

 years and a half! (Can. ent., xi : 201). A more complete statement 

 with details should be given before full credence is given to it. The wood- 

 browns of the chrysalis are evidently protective colors. 



Life history. The history of this butterfly is somewhat different in the 

 northern and southern states. In the south, judging principally from 

 notes furnished by Dr. Chapman of Apalachicola, Fla. , the butterfly hiber- 

 nates, as Doubleday has stated, and lays eggs in the latter half of 

 March and throughout most of April, at the end of which month the 

 hibernating butterflies have disappeared. The eggs hatch in ten days, 

 the caterpillars feed for three or four weeks, the chrysalids hang for from 

 twelve to sixteen days and a first brood of fresh butterflies appears the last 

 of April ; a second brood, after remaining an equal time in chrysalis, 

 appears in July, generally, it would seem, in the latter part of the month ; 

 and a third, the chrysalis state of which is shorter by several days, but 

 which lasts in Cuba ten or eleven days, according to Gundlach, before the 

 middle of September ; fresh specimens continue to emerge from the chry- 

 ealis until nearly the end of October and these all hibernate. The perfect 



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