THE NATURALIST ON THE RIVER AMAZONS. 



'this neighborhood, the males of which pro 

 duce a very loud and not unmusical noise by 

 rubbing together the overlapping edges of 

 their wing-cases. The notes are certainly 

 the loudest and most extraordinary that I 

 ever heard produced by an orthopterous in- 

 sect. The natives call it the Tanana, in allu- 

 sion to its music, which is a sharp, resonant 

 stridulajlion resembling the syllables ta-na-na, 

 tu-na-na, succeeding each other with little 

 intermission. It seems to be rare in the 

 neighborhood. When the natives capture 

 one, they keep it in a wicker-work cage for 

 the sake of liearing it sing. A friend of 

 mine kept one six days. It was lively only 

 for two or three, and then its loud note could 

 be heard from one end of the village to the 

 other. When it died, he gave me the speci- 

 men, the only one I was able to procure. It 

 is a member of the family Locustidse, a group 

 intermediate between the Crickets (Achetidae) 

 and the Grasshoppers (Acridiida3). The total 

 length of the body is two inches and a quar- 

 ter ; when the wings are closed, the insect 

 has an inflated vesicular or bladder-like 

 shape, owing to the great convexity of the 

 thin, but firm, parchmenty wing-cases, and 

 the color is wholly pale green. The instru- 

 ment by which the Tanana produces its 

 music is curiously contrived out of the ordi- 

 nary nervures of the wing-cases. In each 

 wing-case the inner edge, near its origin, has 

 a horny expansion or lobe ; on one wing (b) 

 this lobe has sharp raised margins ; on the 

 other (a), the strong nervure which traverses 

 the lobe on the other side is crossed by a 

 number of fine sharp furrows like those of a 

 file. When the insect rapidly moves its 

 wings, the file of the one lobe is scraped 

 sharply across the horny margin of the other, 

 "thus producing the sounds, the parchmenty 

 wing-cases and the hollow drum-like space 

 which they enclose assisting to give resonance 

 "to the tones. The projecting portions of both 

 wing cases are traversed by a similar strong 

 nervure, but this is scored like a file only in 

 one of them, in the other remaining perfectly 

 smooth. Other species of the family to 

 which the Tanana belongs have similar 

 striclulating organs, but in none are these so 

 highly developed as in this insect ; they ex- 

 ist always in the males only, the other sex 

 having the edges of the wing-cases quite 

 straight and simple. The mode of produc- 

 ing the sounds, and their object, have been 

 Investigated by several authors with regard 

 to certain European species. They are the 

 call-notes of the males. In the common 

 field-cricket of Europe, the male has been ob- 

 served to place itself, in the evening, at the 

 entrance of its burrow, and stridulate until a 

 female approaches, when the louder notes 

 are succeeded by a more subdued tone, while 

 the successful musician caresses with his an- 

 tenna? the mate he has won. Any one who, 

 will lake the trouble, may observe a similar 

 proceeding in the common house-cricket. 

 The nature and object of this insect music 

 are more uniform than the structure and situ- 

 ation of the instrument by which it is pro- 



673 



duced. This differs in each of the three 

 allied families above mentioned. In the 

 crickets the wing- cases are symmetrical ; 

 both have straight edges and sharply scored 

 nervures adapted to produce the stridulation. 

 A distinct portion of their edges is not, there- 

 fore, set apart for the elaboration of a s&und- 

 produoing instrument. In this family the 

 wing-cases lie flat on the back of the insect, 

 and overlap each other for a considerable 

 portion of their extent. In the Locustidae 

 the same members have a sloping position on 

 each side of the body, and do not overlap, 

 except to a small extent near their bases ; it 

 is out of this small portion that the stridu- 

 lating organ is contrived. Greater resonance 

 is given in most species by a thin transparent 

 plate, covered by a membrane, in the centre 

 of the overlapping lobes. In the Grasshop- 

 pers (Acridiidae) the wing-cases meet in a 

 straight suture, and the friction of portions 

 of their edges is no longer possible. But na- 

 ture exhibits the same fertility of resource 

 here as elsewhere ; and, in contriving other 

 methods of supplying the males with an in* 

 strument for the production of call-notes, in- 

 dicates the great importance which she at- 

 taches to this function. The music in the 

 males of the Acridiidae is produced by the 

 scraping of the long hind thighs against the 

 horny nervures of the outer edges of the 

 wing-cases, a drum-shaped organ placed in 

 a cavity near the insertion of the thighs being 

 adapted to give resonance to the tones. 



I obtained very few birds at Obydos. 

 There was no scarcity of birds, but they were 

 mostly common Cayenne species. In early 

 morning the woods near my house were quite 

 animated with their songs an unusual thin^r 

 in this country. I heard here for the first 

 time the pleasing wild notes of the Carashue, 

 a species of wild thrush, probably the Mimus 

 lividusof ornithologists. I found it afterward 

 to be a common bird in the scattered woods 

 of the campo district near Santarem. It is a 

 much smaller and plainer-colored bird than 

 our thrush, and its song is not so loud, 

 varied, or so long sustained ; but the tp2C is 

 of a sweet and plaintive quality, which har- 

 monizes well with the wild and silent wood- 

 lands, where alone it is heard, in the morn- 

 ings and evenings of sultry tropical days. In 

 course of time the song of this humble thrush 

 stirred up pleasing associations in my mind, 

 in the same way as those of its more highly, 

 endowed congeners formerly did at home. 

 There are several allied species in Brazil ; in 

 the southern provinces they are called Sa- 

 biahs. The Brazilians are not insensible to 

 the charms of this their best songster, for I 

 often heard some pretty verses in praise of 

 the Sabiah, sung by. young people to the ac- 

 companiment of the guitar. I found several 

 times the nest of the Carashue, which is built 

 of dried grass and slender twigs, and lined 

 with mud ; the eggs are colored and spotted 

 like those of our blackbird, but they are con- 

 siderably smaller. I was much pleased with 

 a brilliant little red headed rnannikin which 

 I shot .here (Pipra cornutaj. There were 



