299 
ON THE LIFE HISTORY OF A NEW GREGARINE: 
PYX IN IA AN OBI I N. SP. INTESTINAL PARASITE 
OF ANOBIUM PANICEUM L. (COLEOPTERA). 
By MARY VINCENT. 
(From the Molteno Institute for Research in Parasitology , 
University of Cambridge.) 
(With 5 Text-figures.) 
This gregarine was found inhabiting the alimentary canal, and especially the 
midgut, of both larvae and imagines of Anobium, 'paniceum,. All the larvae 
examined, and most of the adult beetles, were found to be very heavily in¬ 
fected, and in some of the larvae almost every epithelial cell harboured one 
or more of the cephalont stages of the parasite (Fig. 1). The lumen of the 
Fig. 1. Section through p.art of the mesenteron of Anobium paniceum showing cephalonts of 
P. anobii attached to the epithelial cells, x 490. 
midgut of these larvae was densely packed with the freely moving sporonts, 
and a number of newly formed cysts were visible in the hindgut. In the imago 
only the cephalont stages were observed, and no sporonts or cysts have been 
found. 
Alimentary Canal of Host. 
The alimentary canal of the larva of Anobium is considerably longer than 
the larva itself, and consequently is much coiled. The foregut is short and 
passes by the oesophageal valve into the much wider mesenteron. In the 
midgut three regions may be distinguished. The first is short with its walls 
