96 



stouter spines. Test, 4 to 550 mm long : 3 to 3*50 mm. broad. 

 Insect 3'5o to 5 mm. long : 2 50 to 3*25 mm. broad. 



Adult S not observed 



Male puparium (fig 3, e) a remarkably ornamental object when 

 perfect ; but the waxy laminae are very brittle and easily detached. 

 Anterior extremity with a single fluted plate marked like the valve of 

 a cockle shell. Median dorsal area occupied by an elongate plate 

 with a prominent central compressed cone surrounded by radiat- 

 ing ribs. Posterior part covered by a large heart-shaped sHghtly 

 concave plate, forming a valve for the exit of the imago, the apex 

 pointed and cleft, with a median conical prominence and radiating 

 lines. The sides occupied by wing-like laminae of striated wax, two 

 on each side. The whitish radiating lines and bars give the scale the 

 appearance of being ribbed or fluted : but the surface is in reality 

 quite smooth and glassy, the paler markings lying below this trans- 

 parent surface. Length, 2 mm. 



Habitat: On twigs of Thespesia populnea (fig. 3,/) : Rames- 

 waram Island, South India. 



This insect, in the form of the test, approaches /. /{? 5^5 z7u > Mask., 

 but differs in the possession of well developed legs. 



Tachavdia, 



It has been customary, in describing species of the genus Tachar- 

 diay to speak of the *' lac-tubes ", presuming these organs to be 

 principally concerned in the secretion of the lac with which these 

 insects invest themselves. I believe this to be a mistaken assumption. 

 A study of the early stages of the insect shows that the lac is exuded 

 from the general surface of the skin. It first appears, in the larva, 

 in the form of separate plates on the dorsal surface of the several 

 segments in the same manner as the waxy matter of Ceroplastes com- 

 mences in isolated waxy plates, afterwards increasing in area and 

 coalescing. No definite glands can be distinguished as responsible 

 for the secretion, just as no definite glands can be shown to be re- 

 sponsible for the dense waxy covering of Ceroplastes, In fact, these 

 dorsal prominences, which may be more justly styled the stigmatic 

 processes, are, with the caudal extremity, the only parts from which no 

 lac is produced. Their extremities are provided with glands of the 

 same nature as those appearing on the chitinous plates of the anal 

 ring, the function of which appears to be the secretion of waxy fila- 

 ments insulating those parts, preventing the accretion of lac there 



