The goal for this volume is to provide an up-to-date review of the discriminative stimulus properties of major psychoactive drug classes with an emphasis on how this paradigm enhances our understanding of these drugs and how these findings translate from animals to humans. The drug discrimination paradigm applies to both drugs of abuse and drugs for treating mental illnesses, and research from these studies has provided immense translational value for learning about the mechanisms responsible for drug effects in humans.

Miss Polly Harrington entered her kitchen a little hurriedly this June morning. Miss Polly did not usually make hurried movements; she specially prided herself on her repose of manner. But to-day she was hurrying-actually hurrying. Nancy, washing dishes at the sink, looked up in surprise. Nancy had been working in Miss Polly's kitchen only two months, but already she knew that her mistress did not usually hurry.

Della Wetherby tripped up the somewhat imposing steps of her sister's Commonwealth Avenue home and pressed an energetic finger against the electric-bell button. From the tip of her wing-trimmed hat to the toe of her low-heeled shoe she radiated health, capability, and alert decision. Even her voice, as she greeted the maid that opened the door, vibrated with the joy of living. "Good morning, Mary. Is my sister in?" "Y-yes, ma'am, Mrs. Carew is in," hesitated the girl; "but-she gave orders she'd see no one." "Did she? Well, I'm no one," smiled Miss Wetherby, "so she'll see me. Don't worry-I'll take the blame," she nodded, in answer to the frightened remonstrance in the girl's eyes. "Where is she-in her sitting-room?" "Y-yes, ma'am; but-that is, she said-" Miss Wetherby, however, was already halfway up the broad stairway; and, with a despairing backward glance, the maid turned away.

There was a thoughtful frown on the face of the man who was the possessor of twenty million dollars. He was a tall, spare man, with a fringe of reddish-brown hair encircling a bald spot. His blue eyes, fixed just now in a steady gaze upon a row of ponderous law books across the room, were friendly and benevolent in direct contradiction to the bulldog, never-let-go fighting qualities of the square jaw below the firm, rather thin lips. The lawyer, a youthfully alert man of sixty years, trimly gray as to garb, hair, and mustache, sat idly watching him, yet with eyes that looked so intently that they seemed to listen. For fully five minutes the two men had been pulling at their cigars in silence when the millionaire spoke. "Ned, what am I going to do with my money?" Into the lawyer's listening eyes flashed, for a moment, the keenly scrutinizing glance usually reserved for the witness on the other side. Then quietly came the answer. "Spend it yourself, I hope-for some years to come, Stanley."

Calderwell had met Mr. M. J. Arkwright in London through a common friend; since then they had tramped half over Europe together in a comradeship that was as delightful as it was unusual. As Calderwell put it in a letter to his sister, Belle: ''We smoke the same cigar and drink the same tea (he's just as much of an old woman on that subject as I am ), and we agree beautifully on all necessary points of living, from tipping to late sleeping in the morning; while as for politics and religion-we disagree in those just enough to lend spice to an otherwise tame existence.'' Farther along in this same letter Calderwell touched upon his new friend again.

''I, Bertram, take thee, Billy, '' chanted the white-robed clergyman. '''I, Bertram, take thee, Billy, ' ''echoed the tall young ridegroom, his eyes gravely tender. ''To my wedded wife.'' '''To my wedded wife.''' The bridegroom's voice shook a little. ''To have and to hold from this day forward.'' ''To have and to hold from this day forward.'' Now the young voice rang with triumph. It had grown strong and steady. ''For better for worse.'' ''For better for worse.'' ''For richer for poorer, '' droned the clergyman, with the weariness of uncounted repetitions.