CONSTITUTION AND DEVELOPMENT OP TERMITES. 57 



other, but careful comparison shows the last to be a little 

 longer than the penultimate, and the third to be very variable. 

 The antennae, which do not differ in the sexes, are very fragile. 

 The maximum number of joints in the adult is nineteen, and is 

 less in the larva. 



[The translator has studied the arrangement of the antenna 

 joints in a very large species of Embiidse from Trinidad, 

 recently described by M, de Saussure (' J. Trinidad Club,' ii, 

 p. 293, 1896) under the name Embia urichi, but really 

 discovered by Mr. J. H. Hart, F.L.S Their number does not 

 exceed twenty-five in any example ; they are blackish in the 

 male, fuscous in the female with pale articulations ; the apical 

 joints are white, but the last is tipped with black and differs 

 slightly in shape. Its presence serves to show whether the 

 antenna is intact at the time of examination. The number 

 of joints present in the intact antenna may vary, irrespec- 

 tive of sex, from fifteen to twenty-five, and may differ on 

 the two sides ,• when it is small there is an increase in the 

 length of the individual joints, so that the average length of 

 the organ does not vary proportionately with their number. 

 It may, perhaps, be assumed that antennae presenting 

 unusually few joints have been broken at an early period, 

 and subsequently regenerated ; but it is a curious circum- 

 stance that the number of white apical joints is roughly 

 proportional to the whole number present. Antennae of 

 15 — 18 joints have only two white apical joints (counting the 

 last) ; antennae of 19 — 20 joints have three (rarely four) white 

 joints ; and antennae of 22 — 25 joints have four (rarely five) 

 white joints. So generally is this the case that in one 

 example the left antenna has twenty-three joints, of which 

 the apical half of the nineteenth is pale, and the twentieth to 

 the twenty-third white ; and the right antenna has twenty-two 

 joints, of which the entire nineteenth is pale, and the last three 

 are white. The blackish (basal) and white (apical) portions 

 thus possess a certain constant ratio of length to each other 

 independently of the number of joints, which may vary in 

 each portion ; and it therefore appears probable that if this 



