106 bulletin: museum of comparative zoology. 



troublesome to the horses and cattle, — became common, and the call 

 of Cicadas became a characteristic sound iu the forests, whereas not one 

 had been heard before. This is the kind of weather the Indians depend 

 upon for drying their milpas, and early in April they began burning 

 them on all sides. The air soon became hazy with smoke, and from the 

 summit of the Castillo great ascending colunms could be seen in all 

 directions as far as the eye could see. 



Field work in Yucatan is made extremely uncomfortable by the 

 abundance, especially in regions where cattle are allowed to run in the 

 woods, of small ticks, locally known as garrapatas. These hang in 

 clusters on the bushes and become brushed upon the clothes in count- 

 less thousands. Even with the greatest precaution great numbers of 

 them find their way beneath the clothes, where they bury their heads in 

 the skin and cause an irritation which at times becomes almost unbeai- 

 able. Furthermore, nearly all the mammals and larger birds are 

 covered with them, so tliat in making up the skins of these animals 

 one receives a further supply of the ticks. The only remedy that was 

 found to be at all efficacious was the free application of kerosene oil. 

 It is said that during the summer months these pests almost, or even 

 completely, disappear. 



In conclusion, I cannot express too strongly my sense of indebtedness 

 to both Mr. and Mrs. Thompson for their kindness and hospitality 

 during my stay at Chicheu-Itza, and in fact during the whole time that 

 I was in Yucatan. A large room was placed entii-ely at m}'^ disposal, 

 and everything was done that could be to aid my work. Only one who 

 has gone into a strange country where an unfamiliar tongue is spoken 

 can appreciate the advantage of having the constant aid and advice of 

 those familiar with the country and its inhabitants. 



2. MAMMALIA. By Glover M. Allen. 



Specimens representing twenty species of mammals were obtained by 

 Mr. Cole during his stay iu Yucatan. Although none of these appears 

 to be undescribed, several are of considerable interest on account of their 

 rarity in collections. The list follows : — 



DIDELPHIDAE. 

 1. Didelphis yucatanensis Allen. 

 The single specimen, a male, obtained March 31, 1905, is from the type 

 locality, Chichen-Itza. The measurements taken by Mr. Cole from the fresh 

 specimen are: length, 690 mm.; tail, 315 mm. ; hind foot, 56 mm. 



