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ately to the Director of the Forestry Station at Olokemeji to place 

 the facilities of the station at our disposal. The following two 

 days were spent investigating frnit conditions around Lagos. Only 

 cultivated fruits were observed and these were scarce. Most of 

 the fruits were green, but we found a few ripe mangoes and some 

 pitanga cherries which yielded the Mediterranean fruit flies in 

 small numbers. A single specimen of an undetermined Opius was 

 captured alive by Mr. Bridwell in the Experimental Gardens at 

 Ebute-Metta. On the morning of July 27 we took the train from 

 Lagos for Olokemeji, about one hundred miles inland, arriving in 

 the afternoon and were met at the station by Mr. R. E. Dennett, 

 acting director, who installed us temporarily in the residence of 

 the director and later gave us an unoccupied house on a neigh- 

 boring hill in the midst of the native forests, to use as a residence 

 and laboratory. By the 29th we were settled down to work. From 

 this date to the 17th of August our time Avas spent in making- 

 daily searches through the forests and fields in the neighborhood 

 of Olokemeji for fruit infested with fruit fly maggots, and collect- 

 ing and studying as far as possible the hymenopterous parasites 

 of that region. We were unable to find all the cultivated fruits in 

 the forestry station grounds referred to by Prof. Silvestri, but 

 daily ran across some new and unfamiliar fruit in the forests, some 

 of which contained maggots. In open and neglected places over- 

 grown with weeds and in a few abandoned fields we found one 

 fruit very abundant— a small cucurbit of the genus Momordica 

 which contained trypetid larvae, and on the Saturday after our 

 arrival I observed and captured a few individuals of the small 

 chalcid parasite described by Prof. Silvestri as TetrasUchus gif- 

 farcli, on fruit of this cucurbit. As this parasite was considered 

 by Silvestri to be one of the most efficient checks on the multiplica- 

 tion of fruit flies in Africa, and as we had been especially com- 

 missioned to get it on this occasion, I immediately set to work to 

 gather all the fruits of this plant that I could find, and inside of 

 a week had several thousand pupae out of them. It is a peculi- 

 arity of the parasite referred to that the later stages of its devel- 

 opment can be observed through the skin of the host, and our de- 

 light was boundless when at the expiration of ten davs we could 

 see that a lars^e proportion of the pui^ae we had collected were 

 parasitized. By the 15th of the month we had several thousand 

 additional pu])ae, and as we had planned on comming out to colon- 

 ize this parasite in the Cauaries in the fall and send it by mail 

 to Honolulu through the Avinter, I immediately made ]>lans to 

 leave for the Canary Islands. Such equi])nient as was needed 

 was hastily got together and packi'd along with all the parasitic 

 material that could be obtained, and on the morning of the 18th I 

 took the train for Lngos, sailing tlie following day on the S. S, 



