154 [J«iy. 



encloses the muscles of flight, etc., appertaining to that division of the 

 thorax. There is, therefore, a free passage for air between the pronotal 

 plate and tlie mesonotum. 



Reverting to the larvae, there are three other points that should be 

 noted. First, there are no ocelli in any of the larval instars, but these 

 appear at the last moult, giving, one must suppose, some additional per- 

 ceptive power to the imago, to Avhich it has been till then a stranger. 

 Secondly and thirdly, at the same moult occurs a multiplication in seg- 

 mentation in both antennae and tarsi. Throughout larval life the 

 antennae are four-jointed, but at the last moult, the second joint 

 becomes divided into two, so that the imago has five joints, an arrange- 

 ment which must at least increase the flexibility of the organ, and so 

 possibl}^ augment its sensitiveness, and the tarsi, which throughout the 

 immature life have had but two joints, get an additional one by the sub- 

 division of the terminal, thereby gaining a more workmanlike instrument 

 for its use. 



The life-cycle of this insect seems to be rather different from that 

 of the rest of our Pentatomidae. The majority certainly pass the 

 winter in the adult condition, but that does not seem to be the case with 

 this species. As above mentioned, eggs found in late August hatched in 

 September, and this would hardly leave time for the maturation of the 

 insect before the change of weather and the state of vegetation rendered 

 vmdesirable a life in the open. The onlj^ records I have been able to 

 gather for the capture of the imago lie between the beginning of June 

 and the end of October ; there is but one outside the limit of those 

 months, and that is May 30th, 1917 (^Edmonds). The absence of 

 records for all the rest of the year seems to imply that the Insect retires 

 into obscurlt}^ as a larva towards the end of October, passes the winter 

 months in a state of inactivity, and emerges again in spring-time to com- 

 plete its larval life before midsummer. This is confirmed by the 

 occurrence of numbers of fully-grown larvae in June ; Commander 

 Walker, speaking of the New Forest in June, says : — " The abundance 

 of tlie nymphs of Tropicoris {Peniatoma) riifipes was quite a feature 

 of the collecting, twent}^ or thirty of these at a time coming down into 

 the umbrella when an oak was beaten " (Ent. Mo. Mag., Aug. 1917). 

 Probably the perfect insects are most numerous in August; I have 

 found recently matured specimens in cop. in August on birch-trees ; but 

 on opening the body of the $ , I could find no trace of ova. If the 

 course sketched above is correct, it gives a shorter imaginal life to this 

 large Pentatomid than is found in an}^ other of our species in the family, 

 a life of not more than five months. 



