1932 ] Notes on Cuban Wasps and their Parasites 11 
cocoon near the top, then softens the clay with a liquid 
secreted from the mouth. The adult also excretes some 
tiny white elongate pellets, presumably from the anus. 
This is the fifth distinct excretory or secretory product, 
the others being the silken part of the cocoon (from the 
mouth), the meconium or stercoral plug (from the anus), 
the excretion or secretion which permeates the silk (from 
the mouth ?), and the secretion which softens the clay cell. 
Associated with Sceliphron assimile were an ichneumonid 
parasite, a dermestid beetle, and a vespid inquiline, Pacho- 
dynerus nasidens (Latr.) . The ichneumonid is Acroricnus 
cubensis (Cress.) [R. A. Cushman]. When Cresson de- 
scribed this species, he noted that it was “parasitic upon 
the larva of Pelopceus lunatus Fab.” Later on in the same 
work (On the Hymenoptera of Cuba), he lists P. lunatus 
as a synonym of P. cxmentarius. I have not seen any 
typical specimens of Sceliphron csementarium from Cuba, 
so Cresson probably considered S. assimile as that species. 
The cocoon of Acroricnus cubensis is obconical, whitish 
or yellowish in color, fuzzy outside and smooth within. The 
meconium is excreted inside the cocoon and is therefore not 
a true stercoral plug. Sometimes a rudimentary cocoon 
is formed within that of the Sceliphron, indicating that 
these larvae did not gain ascendency over their host until 
the resting period of its larva. In these examples, the 
rounded apex of the cocoon is somewhat below that of the 
host cocoon and attached to its wall. Between the apex and 
the conical posterior end which is attached in a similar way, 
there is no apparent indication of any cocoon spun by the 
parasite. 
The dermestid beetles which I found in the nests of 
Sceliphron assimile were determined as Trogoderma sp. 
[A. G. Boving (larvae) , H. S. Barber (adults)]. The 
mature specimens are identical with a form reared by J. C. 
Bridwell from a package of seeds of Sophora stored at 
Brownsville, Texas, in 1921. Mr. Barber’s note is interest- 
ing in this connection. “Several other forms of Trogo- 
derma have been reared from cells of mud wasps about 
buildings and seem to reflect no other connection with these 
