asporogenous

“The systematic interference with these conditions has enabled bacteriologists to induce the development of so-called asporogenous races, in which the formation of spores is indefinitely postponed, changes in vigour, virulence and other properties being also involved, in some cases at any rate.”

Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 2 "Baconthorpe" to "Bankruptcy"

“The four asporogenous species, Enterobacter aerogenes, E. cloacae, Proteus vulgaris and P. mirabilis, and two sporeformers, Bacillus subtilis and B. cereus, were administered orally to T. castaneum larvae by the diet dilution technique (at”

Chapter 8