Skin samples from most body regions of the bowhead whale were examined. The epidermis is 2.7 to 50 times thicker than that reported in other cetaceans with both regional and individual variations in thickness. The thinnest areas examined (1 mm) occur on the eyelid margins and the thickest (25 mm) occur on the lower jaw. A distinctive parakeratotic stratum corneum with a thick underlying stratum spinosum (without a stratum granulosum) extends over the entire body surface. From a few dozen to several hundred epidermal lesions are present on all whales studied. A typical stratum basale of germinative keratinocytes (with melanocytes in pigmented areas) rests upon a well-defined basal lamina. Epidermal rod arrays arise from the basal keratinocytes which cover highly elongated dermal papillae and extend to the epidermal surface through the distal stratum spinosum and the stratum corneum. At least four diatom genera occur on and in the stratum corneum and lesion areas of different whales. The superficial dermis consists of a papillary layer with long (up to 13 mm) dermal papillae interdigitating with the epidermis from a basal area that is 2-4 mm in thickness. The number of dermal papillae per mm2 varies inversely with the thickness of the epidermis. Large diameter, sensory papillae packed with tortuous, highly elongated, encapsulated nerve end organs also interdigitate with the thin epidermal areas of the ventral surface of the rostrum, the upper and lower lip margins, and the upper and lower eyelid margins. Scattered, single, stiff hairs emerge from the skin only in specific, pigmented regions of the head.

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Components of the respiratory system from seven bowhead whales have been examined. The paired and laterally curved external nares are passively closed by a valve-like mass located in the rostral, lateral, and ventral walls of the nasal vestibules. Nasal septal cartilages are paired smooth plates rostrally changing to accordion-like folds caudally. The epiglottic and arytenoidal protuberances of the larynx are typically cetacean, but blunt. The cricoid cartilage is not a complete ring, but an elongated, inverted, trough-shaped structure. The thyroid cartilage is trough-shaped with elongated cranial cornua curving dorsocaudally from each thyroid lamina. A conical mass of skeletal muscle serves as the floor of the short trachea and also surrounds the termination of the laryngeal sac. The trachea is dorsoventrally compressed, lacks a tracheal bronchus, and its width equals its length. The principal bronchi give rise to lobar bronchi at obtuse angles. Large segmental bronchi branch extensively from lobar bronchi near the mediastinal lung surface. The lungs are rectangular and of nearly uniform thickness throughout, without external or internal lobulation.

Management of anterior cruciate ligament (ACL) injury in the dog continues to be a difficult problem in veterinary orthopedics. This experimental study evaluated a reconstructive technique for ACL injury. The technique evaluated was an over‐the‐top procedure using the fascia lata, lateral retinacular tissue, and the lateral one‐third of the patellar tendon as a substitute for the ACL. The results of clinical and pathologic evaluation indicate the technique can be used for reconstruction of the stifle joint following ACL injury.