Pollen cells are surrounded by a thin delicate wall of unaltered cellulose called the endospore or intine, and a tough resistant outer cuticularized wall composed largely of sporopollenin called the exospore or exine. The exine often bears spines or warts, or is variously sculptured, and the character of the markings is often of value for identifying genus, species, or even cultivar or individual. The spines may be less than a micron in length (spinulus, plural spinuli) referred to as spinulose (scabrate), or longer than a micron (echina, echinae) referred to as echinate. Various terms also describe the sculpturing such as reticulate,
What Is This Thing Called Love? What Is This Thing Called Love? "What Is This Thing Called Love?" is a 1929 popular song written by Cole Porter, for the musical "Wake Up and Dream". It was first performed by Elsie Carlisle in March 1929. The song has become a popular jazz standard and one of Porter's most often played compositions. "Wake Up and Dream" ran for 263 shows in London. The show was also noticed in New York, and the critics praised Tilly Losch's performance of the song. The show was produced on Broadway in December 1929; in the American rendition, "What Is This Thing Called