108 THE ENTOMOLOGIST’S RECORD. 
of the highest latitudes and of the extreme limits in which various 
bigenerate and trigenerate species exist and produce more than one 
annual cycle. 
It might be objected that S. Martino is 700 m. high, and that at 
that height emergences might differ less from the northern ones than 
is the case in the Sicilian plain. This difference, however, between 
plain and hills is reduced to a fortnight, which is not surprising, - 
because already in Tuscany it is very small at that height, and because 
as one proceeds further south the effect of altitude, as we have seen, 
always tends to diminish. 
Let us note, therefore, that at S. Martino the first brood of the 
trigenerates is seen to extinguish itself at the same epoch as in Florence, 
except croceus, already extinguished on April 20th, instead of being 
prolonged into May. ‘The second brood of this last as well as that of 
daplidice, emerges from May 5th to June 20th, rather than respectively 
from the end and from the middle of June to the middle of July, as in 
Florence. Of phlaeas and brassicae the second brood has been collected 
at the same epoch as in Florence; of rapae it had not yet appeared on 
June 20th, from which it would seem later than in Florence, and this 
need not surprise us, because the first brood was more abundant in 
May than at Florence, where it chiefly emerges in April and very 
sporadically in May. Also in the case of the following species the 
second brood had not appeared on June 20th; there is no doubt that 
they emerge at the same epoch as in Florence, a little after this date, 
because Ragusa says of some of them that the ‘‘ summer” brood begins 
in June: medon, cleopatra, machaon, and podalirius. Of the bigenerate 
species, pamphilus and cardui emerge until June 20th; the first always 
has the characteristics of the first brood; it follows that its second 
brood does not commence certainly sooner than in Tuscany. The 
second brood of icarus has instead appeared since June 10th instead of 
at the end of the month. Of the annual species atulanta has appeared 
fresh during the first days of May instead of at the end; jurtina 
- is in advance with regard to Florence, and it is an entire month in 
advance, because the g begins on May 12th and the @ on the 28rd; the 
others emerge contemporaneously with Florence: minimus, rubi, 
crameri, cardamines, crataegt, ida, galathea, cinvia, and didyma ; the last, 
however, ceased to emerge on June 10th, whilst at Florence it lasts 
till July 20th. Unfortunately precise data are wanting as to the third 
broods, but, as Ragusa alludes to various trigenerates in August, Sep- 
tember, and October, and we have seen that the first two broods 
correspond with the greatest exactitude to the Tuscan ones, it is to be 
presumed that the brood corresponds equally, or is somewhat delayed 
by a more prolonged ‘‘ summer pause.” 
It is not yet possible to follow the behaviour of all the species with 
regard to the increase of latitude because the data concerning the tri- 
generates, which are naturally the most interesting, do not distinguish 
accurately between the two summer broods, which are nearly always 
confused into one only. We cannot, therefore, decide at what latitude 
their restriction really happens. This must be very different in the 
different species; it is enough to say that phlacas and aeyerta emerge 
three times a year and at the same epochs from Sicily to central 
England, and that rhanmi instead has only one brood all over England. 
The other trigenerates have two broods in the greater part of Central 
