150 The University Science Bulletin. 



hatched at 2:35 p. m. was creamy white with dark-red eyes at 3:12 

 p. m., when a faint pattern began to appear. At 3:35 it was some- 

 what darker and the pattern more distinct. Thus it takes an hour 

 or so for it to attain its characteristic color. 



MOLTING. 



An examination of the life-history tables will indicate that mor- 

 tality at molting time was very great in the rearings. This suggests 

 that conditions were not favorable to normal molting. In the light 

 of R. Takahashi's observations on the Ochteridae, published in Jap- 

 anese,* it may be that Gelastocoris nymphs, like those of Ochterus 

 formosanus Mats., normally fashion for themselves small cells of 

 sand above the ground in which the moltings take place. The sand 

 in the rearing jars was packed, and perhaps too coarse for the 

 nymphs. 



The nymph becomes very plump of body along toward the time 

 to change. Several first-instar bugs were under observation during 

 the process of molting. The bug rests upon the sand, all legs out- 

 spread and apparently rigid. A longitudinal rent appears on the 

 dorsum of the head and thorax, and the greenish or creamy-white 

 nymph begins bulging out, the dorsal part of the thorax leading. 

 Shortly the head is freed, the slit through the old skin extends back 

 to the abdomen and then laterally to the margins of the body. These 

 lateral fissures enable the bug to work his way out. The new form 

 is so much larger than the old exuvium which encased it, that one 

 wonders how it was ever tucked away in so small a fepace. When 

 the new instar is entirely free, the old skin may snap back in place 

 again and look like a perfect nymph, save that the eyes are whitish 

 instead of dark red. 



The following article appeared in Japanese, by R. Takahashi. 

 The observations are so interesting, and relate to a family so little 

 known, that English-reading students will be glad to give Mr. Taka- 

 hashi credit for it. 



These observations pertain to Ochterus jormosanus (Mats.), wliich is not 

 uncommon in Formosa. 



1. The adults Hve upon the sandy shores of ponds and streams, where the 

 colors of their backs merge into their surroundings, rendering them difficult to 

 discover. They are not able to submerge and do not run out upon the water, 

 where they are occasionally found by accident; but the nymphs are amphib- 

 ious, being often seen submerged. 



* R. Takahashi: "Observations on the Ochteridte," Trans. Nat. Hist. Soc. Formosa, vol. 

 XI, No. 55, pp. 119-125 (1921). 



