204 A YEAR OF COSTA RICAN NATURAL HISTORY 



Its antennae (lOO mm.) and maxillary palps (12.5 mm.) was 

 extraordinary. At the farther waterfall were a number of 

 medium-sized "spiny-bellied" spiders {Edricus tricuspis, 

 Acrosoma incequalis, Gasteracantha kochi) whose abdomens 

 presented a great variety of odd shapes, armed with rela- 

 tively large spines. 



A large fresh-water crab, over four inches across the cara- 

 pace and with most formidable pincers, was at the farther 

 waterfall on April 27. He sidled through the stream and 

 up the bank, climbing better than one would expect from so 

 clumsy a creature, and backed into a hole under the roots 

 of trees bared by the water, keeping his pincers out and 

 ready for action. At a little stream still farther on were the 

 very antitheses of this monster — little crabs less than half 

 an inch across. 



About half a mile west of the farther fall was a third fall 

 or rather cascade reached by a little trail through a bit of 

 exceedingly thick damp woods, full of wild ginger, Heli- 

 conias, ferns and caladiums. The place was extremely 

 pretty and ought to be a favorite haunt of many forest-lov- 

 ing species. Here on May 2 we came upon the body of a 

 fair-sized armadillo some time deceased. After long hunt- 

 ing among the fallen leaves and stones of this brook on April 

 27, P. found a dragonfly larva with a pair of finger-like gills 

 on the ventral surface of each of the second to the seventh 

 abdominal segments. Nothing like it was known for any 

 member of this order of insects inhabiting the Americas, but 

 since similar conditions had been described thirty years be- 

 fore for certain Indian Calopteryginae, we at once suspected 

 that this larva might also belong to this subfamily and pos- 

 sibly to the genus Cora, the adults of which we knew to live 

 here. The larvae found on this day and also on April 29 

 had lost their three caudal gills, which although forming 

 part of the proper equipment of Zygopterous larvae, seem to 



