148 ENTOMOLOGICAL SOCIETY 



Jerome Schmidt, Beatty, Pa. ; Mr. David M. Little, 40 Chestnut 

 St., Salem, Mass. 



Professor Riley presented some notes on Margarodes and ex 

 hibited two necklaces made of so-called "ground pearls," one 

 from Montserrat, the other from Jamaica, the former being com 

 posed of larger specimens. The ground-pearls are Coccidae of 

 the genus Margarodes Guilding. He described the finding of these 

 insects in the ground at Montserrat by himself and Mr. Hubbard 

 in February, and detailed further observations by himself upon 

 the same insect in Barbadoes and Jamaica. He read a review of 

 the literature and explained at some length his views as to the 

 formation of the shell. The communication was discussed by 

 Messrs. Hubbard, Uhler, Howard, Stiles, and Riley. Mr. Hub- 

 bard stated that he had started to make a list of the plants on 

 the roots of which Margarodes was found, but they proved to be 

 so numerous that he concluded it would be more feasible to make 

 a list of the plants on the roots of which the insects do not occur. 

 They are found in all soils, from hard volcanic soil to the sand 

 of the sea-beach. The activity of the adult insect was vouched 

 for by Mr. C. A. Barber, superintendent of agriculture in the 

 Leeward Islands, in conversation with Mr. Hubbard. Mr. Hub 

 bard himself had found damaged adults. The broods he found 

 to be well defined. He thinks that the shell of the insect may 

 be compared with the shell of the turtle, and that it is composed 

 of infiltrated cast skins. The larval skin splits, and is shoved up 

 at the apical end, forming a cap, and the previous exuvia are 

 pushed further out and to each side, making a succession of caps 

 and four side tubercles. The filaments, he thinks, are of w r ax, 

 and he has seen them pushed out more than the length of the 

 insect. The shell is apparently chitinous. When placed in 

 strong sulphuric acid it turns black in two days, but if the acid 

 is diluted ever so slightly it does not produce the blackening 

 effect. 



Professor Riley considered the shell to be largely a secretion 

 from definite pores, and that this secretion is, by the pressure of 

 the earth, formed into plates something as in Vinsonia and Cero- 

 plastes. Mi\ Howard stated that the difficulty with this theory 

 is that the secretion of Vinsonia and Ceroplastes is wax, whereas 



