"To air some of my recently acquired entomological knowledge, I may tell you that the moth caterpillar generally goes underground to enter the pupa stage," continued Warriner. "If the transformation does take place at the surface the cocoon is sometimes found under a dead leaf or a fallen branch; still more rarely beneath the bark of a tree. It is virtually impossible that it should have been fixed naturally in such an exposed position as the crack of a door. "Even more significant is the fact that this cocoon is of a species not indigenous to Maryland; in fact, it doesn't belong to this country at all. Come over here," and he led me to the corner in which stood the glass cases containing Richard Hildebrand's famous collection of the _lepidoptera_. Warriner pointed out a magnificent specimen of the Great Peacock moth of Europe, an entomological aristocrat described by the French naturalist, J. H. Fabre, in one of his fascinating essays. Now all the other specimens of the adult butterfly or moth were accompanied by their respective cocoons. But below the Great Peacock was a vacant space. Warriner lifted the lid of the case, and extended his hand for the cocoon that I still held. He fixed it in the empty place. "Certainly it looks as though it belonged there," he said tersely. Effingham came in to take away the tray of pitcher and glasses. "Come here, boy," said Warriner with the confident command of the born and bred Southerner, and Effingham was prompt to obey. "You remember the day Marse Francis died?" "Yassah." "When Miss Eunice sent you up stairs to get the ammonia was she wearing any kind of a wrap?" "Nossah. Dere was a lil' brack shawl er-hangin' on 'er arm; nuffin else." Warriner glanced at me. "Keep that in mind," he said quietly. He turned again to Effingham. "Did she ask you for anything?" he continued. "Nossah." "I believe you're lying to me. Just think it over ... carefully now." With the greatest deliberation Warriner took some strands of coarse green and yellow worsted from his pocket, and proceeded to tie them into an intricate-appearing knot. Effingham watched him with concentrated and fascinated attention. . "Well?" said Warriner sharply, and leaned forward with the variegated knot depending from his forefinger. Effingham shivered, and backed away. "I do 'member one lil' thing," stammered the old man. "Mis' Eunice, she done tole me to-gib 'er----" "The master-key?" "Yassah, dat's ezackly what she done said. She 'splained the doctah might want to go in the liburry befo' I come back." "Then you did give it to Miss Eunice?" "She grabbed it fum me, right outen my han', and tole me to git erlong. An' dat's de whole Gawd's truf, Marse Chalmers." "All right," nodded Warriner, and Effingham retired with every indication that he was glad to get away. "Anything is voodoo to one of the old-time darkies," smiled Warriner. "A bit of colored ribbon and two crossed sticks is a good enough 'cunjer' for almost any emergency."