920 ■ I'EOCEEDINGS OF THE TllinU ENTOMOLOGICAL MEETING 



Just-hatched larva. 2 mm. long, yellow. Head large and provided 

 with strong mandibles, and short antenns^. Close to the base of each 

 antenna and just posterior to it is a gronp of four small e3^e-spots, one 

 below the other. The ultimate segment bears a pair of fleshy pseudopods. 



Mature larva. 8 mm. long : legs very small ; abdomijial segments 

 large and distinct. There is a pair of short chitinous spines on the dorsal 

 surface of the last segment, directed cephalad. The anal pseudopods 

 are prominent. 



Pupa. 7 mm. The newly transformed piq^a is yellow but later on 

 it becomes darker and tinged with reddish-brown at the tips of the 

 appendages. The eyes at first present the appearance of a group of light 

 brown specks but finall}' form into large black dots. A transverse row 

 of spines is preseirt on the dorsal aspect of every abdominal segment 

 except the last one, which has instead a pair of very strong .sjjines occupy- 

 ing a terminal position and curved slightly towards the anterior. The 

 dorsal spines become larger and more pronounced as they approach the 

 posterior end. A pair of sjiiues directed caudad are present on the ventral 

 surface of the seventh abdominal segment. Hairs are found on the 

 vertex, on the anterior and posterior margins of the large prothoracic 

 shield and also interpersed with the dorsal sjDines. 



The total life cycle is : — egg 5 to 6 days, larva 25 days, and pupa 

 14 days. About four days have to elapse after emergence for the beetle 

 to leave the shelter of the stem. 



IV. Habits. 



The eggs are laid singly in the stems at some point from one to six 

 inches above the soil. This takes place during the second mouth of the 

 crop when the stalks are rapidly elongating and the .ears are being put 

 out, and eggs are laid only in stems in which the central hollow has beguii 

 to appear. The egg is thrust in at some spot just within an inch above 

 a node. As elongation of the internode in grasses is confined to the 

 portion just above the no^le this region is softer and more vulnerable 

 than the portion farther up and is therefore selected for oviposition. 



Oviposition always leaves a mark ; though it is often impossible 

 to trace it on tlie stem itself. But on the outer leaf-sheath it remain.* 

 distinct as a small dry oval patch, bearing three punctures in a hori»- 

 zontal row. The side ones seem to be caused by some lateral Supporting 

 structures on the ovipositor. The egg is passed in through the central 

 one and this is therefore the only puncture that extends into the stem. 



There is only one egg laid in an internode and it has its long axis in a 

 line with that of the stem. Though the egg is laid within an inch above 

 a node, due to the rapid elongation of the stem as mentioned above it 



