THE WKITINOS OF M. PABRE. 129 



nccouut of the metamorphoses undergone by those larvae which are 

 fortunate enough on leaving the shell to find their larders weU 

 supplied ; but we must pass on to give a short summary of M. Fabre's 

 paper on the habits and metamorphoses of Sitaris humeralis. 



This interesting beetle is parasitic on Anthopliora, in the galleries 

 of which it lays its eggs. These are hatched at the end of September 

 or beginning of October ; and M. Fabre not umiaturally expected 

 that the young larvae, which are active little creatures with six 

 serviceable legs, would at once eat their way into the cells of the 

 Anthopliora. No such thing: till the month of April following they 

 remain without leaving their birthplace, and consequently without 

 food ; nor do they in this long time change either in form or size. 

 M. Fabi'e ascertained this, not only by examining the burrows of the 

 Anthophoras, but also by direct observation of some young larvfe 

 kept in captivity. In April, however, his specimens at last threw 

 oft' their long lethargy, and hurried anxiously about then prisons. 

 Naturally inferring that they were in search of food, M. Fabre sup- 

 posed that this Avould consist either of the larvae or pupae of the 

 Anthophora, or of the honey with which it stores its cell. All three 

 were tried without success. The two first were neglected, and when 

 placed on the latter they hurried away, or perished in the attempt, 

 being evidently unable to deal with this sticky substance. M. Fabre 

 was in despair : " Jamais experience," he says, " n'a eprouve pareille 

 deconfiture. Larves, nymphes, cellules, miel, je vous ai tout ofiert ; 

 que voulez-vous done, bestioles maudites ?" 



The first ray of light came to him from our countryman, New- 

 port, who ascertained that a small parasite found by Leon Dufour 

 on one of the wild bees, and named by him Triungulinus, was, in 

 fact, the larva of the Meloe. The larvae of Sitaris much resem- 

 bled Dufour's Triungulinus, and acting on this hint, M. Fabre exa- 

 mined many specimens of Anthophora, and found on them the larvae 

 of his Sitaris. The males of Anthophora emerge from the pupae 

 before the females, and as they come out of their galleries, the little 

 larvae fasten upon them. Not, however, for long : their instinct 

 teaches them that they are not yet in the straight path of develop- 

 ment ; and watching their opportunity they pass from the male to 

 the female Bee. Guided by these indications, M. Fabre examined 

 several cells of Anthophora : in some, the egg floated by itself on the 

 surface of the honey ; in others, on the egg of the Anthophora, as on 

 a raft, sat the still more minute larva of the Sitaris. The mystery 

 was solved. By a process of reasoning too long for us to insert, M. 

 Fabre convinced himself that at the moment when the egg is laid, 

 the Sitaris larva springs upon it. Even while the poor mother is 

 carefully fastening up her cell, her mortal enemy is beginning to 

 devour her oft'spring. For the egg of the Anthophora serves not only 

 as a raft, but as a repast. The honey, which is enough for either, 

 would be too little for both ; and tlie Sitaris, therefore, in its first 

 meal, relieves itself from its only rival. After eight days the egg is 



