236 THE VOYAGE OF H.M.S. CHALLENGER. 



females, and secrete a red coloured strongly smelling substance, supposed to act as a 

 soxual attraction. The bat was resting on a bare tree-trunk, asleep, the dense forest 

 growth overhead making this exposed situation quite dark enough for it. 



" On our way back to the farm, we watched some ants carrying on bits of cassava 

 leaves to their holes. One cannot go a walk anywhere in the neighbourhood of Bahia 

 without seeing these Leaf-cutting Ants {CEcodoma) at work. Their habits have been 

 described by many observers, and recently by Mr. Belt 1 at great length. A new 

 Hymenopterous insect (Pepsis collaris, Kirby) 2 was obtained during the excursion. 



" The further road to St. Amaro lay through sugar estates all the way. I left 

 St. Amaro early next morning by steamer, and reached Bahia at 10 a.m." 



During the stay at Bahia the steam pinnace was engaged several days dredging in the 

 bay. In some places the deposit was a white quartz sand, containing fragments of 

 felspar, mica, magnetite, hornblende, and other minerals, and also fragments of Echino- 

 derms, Polyzoa, Serjmlce, and other organisms. In other places it was a dark mud, 

 containing, along with fine argillaceous matter, all the above mentioned minerals and 

 organisms. The dredgings were very successful, animals belonging to all the principal 

 invertebrate groups being taken. Astrophytons and Ophiurids were especially abundant. 



1 Thos. Belt, The Naturalist in Nicaragua, p. 71 et seqq., London, John Murray, 1874. 



2 Aim. and Mag. Nat. Hist, ser. 5, vol. xiii. p. 408, 1884- 



