Cervical Plexus," Doctor Benjulia answered as gravely as
ever.

This attempt at mystifying the child failed completely. Zo considered
the unknown tongue in which he had answered her as being equivalent to
lessons. She declined to notice the Cervical Plexus, and returned to the
little terrier at home. "Do you think the dog likes it?" she asked.

"Never mind the dog. Do _you_ like it?"

"I don't know."

Doctor Benjulia turned to Teresa. His gloomy gray eyes rested on her, as
they might have rested on any inanimate object near him--on the railing
that imprisoned the birds, or on the pipes that kept the monkey-house
warm. "I have been playing the fool, ma'am, with this child," he said;
"and I fear I have detained you. I beg your pardon." He pulled off his
episcopal hat, and walked grimly on, without taking any further notice
of Zo.

Teresa made her best courtesy in return. The magnificent civility of the
ugly giant daunted, while it flattered her. "The manners of a prince,"
she said, "and the complexion of a gipsy. Is he a nobleman?"

Zo answered, "He's a doctor,"--as if that was something much better.

"Do you like him?" Teresa inquired next.

Zo answered the duenna as she had answered the doctor: "I don't know."

In the meantime, Ovid and his cousin had not been unobservant of what
was passing at a little distance from them. Benjulia's great height, and
his evident familiarity with the child, stirred Carmina's curiosity.

Ovid seemed to be disinclined to talk of him. Miss Minerva made herself
useful, with the readiest politeness. She mentioned his odd name, and
described him as one of Mrs. Gallilee's old friends. "Of late years,"
she proceeded, "he is said to have discontinued medical practice, and
devoted himself to chemical experiments. Nobody seems to know much about
him. He has built a house in a desolate field--in some lost suburban
neighbourhood that nobody can discover. In plain English, Dr. Benjulia
is a mystery."

Hearing this, Carmina appealed again to Ovid.

"When I am asked riddles," she said, "I am never easy till the answer
is guessed for me. And when I hear of mysteries, I am dying to have them
revealed. You are a doctor yourself. Do tell me something more!"

Ovid might have evaded her entreaties by means of an excuse. But her
eyes were irresistible: they looked him into submission in an instant.

"Doctor Benjulia is what we call a Specialist," he said. "I mean that
he only professes to trea