152 [July 



kind of maggots. Fragments of boiled Laeon-fat, boiled lisb. potato 

 (cooked), and banana-skin were placed in the breeding-jars. The insects 

 went to the fish at first, but it is uncertain whether they actually ate it. 

 They flocked to the fat, at which they could be seen working their jaws 

 vigorousl^r, with tails curled over their backs as they fed. The potato 

 and banana were ignored. The beetles continued alive and active for 

 some weeks with no other means of sustenance than this and the weekly 

 moistening of the sand. There was no evidence of cannibalism. Though 

 practically all had emerged by the end of November, all (except tlios(! 

 killed for purposes of preservation) were still active, with a solitary 

 exception, on January 2nd. Many specimens, therefore, lived 5 weeks, 

 and the earlier-emerged lived considerably longer. After January 2nd 

 the weekly moistening was stopped, and on January 26th all were found 

 to be dead. 



Wadsworth states that at least two generations of A. hilineata are 

 })roduced annually, and that 3'oung larvae which enter puparia in autumn 

 remain in the first stage all the winter, not moulting to the second stage 

 till about April. It is impossible to say exactly what the cycle of 

 A. (d(]ayum is under natural conditions. In the open, possibly, adults 

 would not emerge from puparia in November as mine did, but might 

 wait till spring. The matter probabl}^ depends on the number of genera- 

 tions of the Phycodromid hosts, adults of which can be seen flying over 

 seaweed on mild days even in mid-winter. 



Sexes of Aleochara algarum. — A few of the beetles made their 

 escape, but out of 96 specimens mounted or preserved in spirit, 45 are 

 males, 42 females, and the sex of the remaining 9 is not determined 

 with certaint}', but most of them are probably males. There is no very 

 ready external means of distinguishing the sexes. I have detected no 

 difference in antennae or tarsi, but by dissecting several specimens the 

 following differences in the hind abdominal segments become visible : — 



(f . Hind margin of 8th dorsal segment more strongly sinuate in tlie 

 middle, with about 6 or 7 widely-separated teeth on either side ; hind margin 

 of 10th dorsal truncated and feebly sinuate; 6th ventral slightly longer, its 

 hind margin foi-ming a steeper curve ; 7th ventral overlapped at the sides by 

 the deflexed lateral pieces of the 9th dorsal, but visible between them as a 

 long, narrow plate, produced ta a rounded apex, which often projects beyond 

 the 10th dorsal and is visible from above, so that the body appears to end in 

 a single blunt apex (the lateral pieces ©f the 9th dorsal do not project as 

 anal stybs). 



5 . Hind maruin of 8th dorsal less strongly, or not at all. sinuate in the 

 middle, t<iol]ied as in c^ ; hind margin of 10th dorsal .similar to that of (^ 



