A Collecting Trip to Colombia 23 



straight or extended parallel to the long fold. Of course careful handling 

 of the envelopes was necessary until the insects were dry, but when, on our 

 return, we opened these envelopes, sometimes containing six insects, we 

 found the specimens beautifully preserved with a minimum amount of dis- 

 tortion. 



In papering aeshnines and gomphines, instead of using the bit of glued 

 cord at one end of the envelope, as is our custom, we usually used some com- 

 mon libelluline with a thorax sufficiently bulky to insure no pressure of the 

 envelope on the abdomen of the other specimen. This worked as well as 

 the glued cord and reduced the number of envelopes required to paper the 

 day's catch. 



In papering libellulines, in which it is desirable that the legs should 

 not cover nor obstruct the view of the accessory genitalia, it was found that 

 by taking the opened envelope in the left hand and by holding the wings of 

 the insect with tweezers in the right hand, it was possible, without loss of 

 time in papering, to brush the legs of the insect forward, over the edge of 

 the envelope, thus entirely clearing the genitalia. This may seem a small 

 matter except to one who has had occasion to examine the genitalia of a few 

 hundred or thousand libellulines. 



During our trip some of our killing bottles became "weak," and in 

 several instances inert but not dead specimens were placed in the ordinary 

 letter envelopes in the collecting box for transportation during the day. Such 

 specimens, when they revived, chewed and tore other specimens placed in 

 the envelopes with them. This was guarded against by using "strong" bot- 

 tles for killing and weaker bottles for carrying material till a sufficient num- 

 ber had accumulated to justify opening the collecting box. Specimens with 

 broken necks, caused by twisting the head, will not damage other specimens. 



While papering material at night it was found that if the letter en- 

 velopes were white or light colored one could more readily see whether or not 

 they were emptied of all specimens, since, in poor light, any insect clinging 

 to the inside of an envelope is more readily seen in or through a white 

 envelope. It was found desirable to letter or number these envelopes, desig- 

 nating three or four groups. For example, each one-fourth of the envelopes 

 would be plainly labelled A, B, C, and D, respectively. In the field it is ad- 

 visable that the specimens gathered in the same habitats or localities be placed 

 in the envelopes similarly lettered. Such a procedure will facilitate paper- 

 ing the material in properly designated envelopes when the day's collecting is 

 over. Other conditions also arise where separation of material during the 

 day is desirable. Of course variously colored envelopes are even better than 

 lettered or numbered envelopes, except for the reason given above for pre- 

 ferring white envelopes. 



COMMON NAMES OE DRAGONFLIES 



Mr. H. L. Tyrer, of Barranquilla, told us that so far as he knew caballito 

 was the only name in common use in Colombia. At any rate in our limited 

 experience we always found this name readily understood. Young men 

 travelling with us on one of the river steamers told us that at Medellin 



