Regarding John Espey's review of "The Haiku Handbook" by William J. Higginson with Penny Harter, either Espey or the author of the book has blundered. Espey writes, "He (Higginson) explains and defines the forms of the Tanka , the Renga , the linked verse stanzas of the Senryu . . . ."
Now Renga , not Senryu , is defined as linked verse by every Haikuist I have ever known or read about. Senryu is a comic or satiric form of Haiku, i.e. three lines of five-seven-five syllables respectively that do not necessarily include a seasonal theme as should Haiku.
Here's a brief rundown on Japanese verse: Tanka developed first and predates the more familiar Haiku by nearly 1,000 years. From the earliest times Tanka was composed in five lines of five-seven, five-seven, seven syllables, the first pair of lines treating one thought, the second pair dealing with another, and the last line serving as a refrain or reiteration. But as time passed, it began to be written in a five-seven-five, seven-seven pattern that in time became the "modern" Haiku. During the slow transformation of the Tanka to the Haiku, there arose a verse form called Renga or linked verse. Single link Renga was a form of Tanka usually written by two people, one writing the first (five-seven-five) section and the other adding the second (seven-seven) section. The name Hokku was used for this first section in a chain of Renga that could stretch out quite long . . . . Since the first verse set the tone of that which followed, it was considered the most important and began to stand alone, and so Haiku was born.